LM95214CISD/NOPB - NATIONAL SEMICONDUCTOR

Temperature (°C)

Temperature Error (°C)

-50 -30 -10 10 30 50 70 90 110 130

-0.25

0.25

0.5

0.75

1.25

D003

3.0V

3.3V

3.6V

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An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.

LM95214

SNIS146B –MARCH 2007–REVISED OCTOBER 2017

LM95214 Quad Remote Diode and Local Temperature Sensor With SMBus Interface

1 Features

1• Accurately Senses Die Temperature of 4 Remote

ICs or Diode Junctions and Local Temperature

• Local Temperature Accuracy ±2.0°C (Maximum)

• Remote Diode Temperature Accuracy ±1.1°C

(Maximum)

• Supply Voltage: 3 V to 3.6 V

• Average Supply Current (1-Hz Conversion Rate)

0.57 mA (Typical)

• Programmable Digital Filters and Analog Front-

End Filter

• 0.125°C LSB Temperature Resolution

• 0.03125°C LSB Remote Temperature Resolution

With Digital Filter Enabled

• Signed Format: +127.875°C/–128°C Remote

Range

• Unsigned Format: 0°C/255°C Remote Range

• Remote Diode Fault Detection, Model Selection,

and Offset Correction

• Mask and Status Register Support

• 3 Programmable TCRIT Outputs With

Programmable Shared Hysteresis and Fault-

Queue

• Programmable Conversion Rate and Shutdown

Mode One-Shot Conversion Control

• SMBus 2.0 Compatible Interface, Supports

TIMEOUT

• Three-Level Address Pin

2 Applications

• MCU, GPU, ASIC, FPGA, DSP, and CPU

Temperature Monitoring

• Telecommunication Equipment

• Servers and Personal Computers

• Cloud Ethernet Switches

• Secure Data Centers

• Highly Integrated Medical Systems

• Precision Instruments and Test Equipment

• LED Lighting Thermal Control

• Office Electronics

• Electronic Test Equipment

• Processor and Computer System Thermal

Management

3 Description

The LM95214 device is an 11-bit digital temperature

sensor with a 2-wire System Management Bus

(SMBus) interface that can very accurately monitor

the temperature of four remote diodes as well as its

own temperature. The four remote diodes can be

external devices such as microprocessors, graphics

processors that target the ideality of a 2N3904

transistor or diode-connected 2N3904s.

The LM95214 reports temperature in two different

formats for +127.875°C/–128°C range and 0°C/255°C

range. The LM95214 TCRIT1, TCRIT2 and TCRIT3

outputs are triggered when any unmasked channel

exceeds its corresponding programmable limit and

can be used to shutdown the system, to turn on the

system fans or as a microcontroller interrupt function.

The current status of the TCRIT1, TCRIT2, and

TCRIT3 pins can be read back from the status

registers. Mask registers are available for further

control of the TCRIT outputs.

Two LM95214 remote temperature channels have

programmable digital filters while the other two

remote channels use a fault-queue to minimize

unwanted TCRIT events when temperature spikes

are encountered.

For optimum flexibility and accuracy, each LM95214

channel includes registers for offset correction. A

three-level address pin allows connection of up to 3

LM95214s to the same SMBus master. The LM95214

includes power saving functions such as:

programmable conversion rate, shutdown mode, and

disabling of unused channels.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)

LM95214 WSON (14) 4.00 mm × 4.00 mm

(1) For all available packages, see the orderable addendum at

the end of the data sheet.

Remote 1 Temperature Error, TA=TD

LM95214

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Table of Contents

1 Features.................................................................. 1

2 Applications ........................................................... 1

3 Description............................................................. 1

4 Revision History..................................................... 2

5 Pin Configuration and Functions......................... 3

6 Specifications......................................................... 4

6.1 Absolute Maximum Ratings ...................................... 4

6.2 ESD Ratings.............................................................. 4

6.3 Recommended Operating Conditions....................... 5

6.4 Thermal Information.................................................. 5

6.5 Electrical Characteristics: Temperature-to-Digital

Converter .................................................................. 5

6.6 Logic Electrical Characteristics: Digital DC

Characteristics ........................................................... 6

6.7 Switching Characteristics: SMBus Digital................. 7

6.8 Typical Characteristics.............................................. 8

7 Detailed Description............................................ 10

7.1 Overview................................................................. 10

7.2 Functional Block Diagram....................................... 10

7.3 Feature Description................................................. 11

7.4 Device Functional Modes........................................ 20

7.5 Register Maps......................................................... 23

8 Application and Implementation ........................ 38

8.1 Application Information............................................ 38

8.2 Typical Application.................................................. 38

8.3 Diode Non-Ideality................................................... 39

9 Power Supply Recommendations...................... 42

10 Layout................................................................... 43

10.1 Layout Guidelines ................................................. 43

10.2 Layout Example .................................................... 43

11 Device and Documentation Support................. 44

11.1 Receiving Notification of Documentation Updates 44

11.2 Community Resources.......................................... 44

11.3 Trademarks........................................................... 44

11.4 Electrostatic Discharge Caution............................ 44

11.5 Glossary................................................................ 44

12 Mechanical, Packaging, and Orderable

Information........................................................... 44

4 Revision History

NOTE: Page numbers for previous revisions may differ from page numbers in the current version.

Changes from Revision A (March 2013) to Revision B Page

•Added Device Information table, Added ESD Ratings table, Feature Description section, Device Functional Modes

section, Application and Implementation section, Specification section, Detailed Description section, Layout section,

Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section. .................. 1

Changes from Original (March 2013) to Revision A Page

• Changed layout of National Data Sheet to TI format ........................................................................................................... 43

LM95214

TCRIT3NC 141

VDD SMBCLK2 13

D4+ SMBDAT3 12

D3+ TCRIT24 11

D- TCRIT15 10

D2+ A06 9

D1+ GND7 8

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5 Pin Configuration and Functions

NHL Package

14-Pin WSON

Top View

Pin Functions

PIN DESCRIPTION

NO. NAME

1 NC No Connect

Not connected. May be left floating, connected to GND or VDD.

2 VDD

Positive Supply Voltage Input

DC Voltage from 3.0 V to 3.6 V. VDD must be bypassed with a 0.1-µF capacitor in parallel with 100 pF. The 100-

pF capacitor must be placed as close as possible to the power supply pin. Noise must be kept below 200 mVp-p,

a 10-µF capacitor may be required to achieve this.

3 D4+

Diode Current Source

Fourth Diode Anode. Connected to remote discrete diode-connected transistor junction or to the diode-

connected transistor junction on a remote IC whose die temperature is being sensed. A capacitor is not required

between D4+ and D–. A 100 pF capacitor between D4+ and D– can be added and may improve performance in

noisy systems. Float this pin if this thermal diode is not used.

4 D3+

Diode Current Source

Third Diode Anode. Connected to remote discrete diode-connected transistor junction or to the diode-connected

transistor junction on a remote IC whose die temperature is being sensed. A capacitor is not required between

D3+ and D–. A 100-pF capacitor between D3+ and D– can be added and may improve performance in noisy

systems. Float this pin if this thermal diode is not used.

5 D−Diode Return Current Sink

All Diode Cathodes. Common D– pin for all four remote diodes.

6 D2+

Diode Current Source

Second Diode Anode. Connected to remote discrete diode-connected transistor junction or to the diode-

connected transistor junction on a remote IC whose die temperature is being sensed. A capacitor is not required

between D2+ and D–. A 100-pF capacitor between D2+ and D– can be added and may improve performance in

noisy systems. Float this pin if this thermal diode is not used.

7 D1+

Diode Current Source

First Diode Anode. Connected to remote discrete diode-connected transistor junction or to the diode-connected

transistor junction on a remote IC whose die temperature is being sensed. A capacitor is not required between

D1+ and D–. A 100-pF capacitor between D1+ and D– can be added and may improve performance in noisy

systems. Float this pin if this thermal diode is not used.

8 GND Power Supply Ground -- System low noise ground.

9 A0 Digital Input

SMBus slave address select pin. Selects one of three addresses. Can be tied to VDD, GND, or to the middle of a

resistor divider connected between VDD and GND.

10 TCRIT1 Digital Output, Open-Drain

Critical temperature output 1. Requires pullup resistor. Active LOW.

11 TCRIT2 Digital Output, Open-Drain

Critical temperature output 2. Requires pullup resistor. Active LOW.

12 SMBDAT SMBus Bidirectional Data Line, Open-Drain Output

From and to Controller; may require an external pullup resistor

13 SMBCLK SMBus Clock Input

From Controller; may require an external pullup resistor

14 TCRIT3 Digital Output, Open-Drain

Critical temperature output 3. Requires pullup resistor. Active LOW.

SNP

GND

V+

6.5V

D3 ESD

CLAMP

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Table 1. ESD Protection

PIN NO. LABEL CIRCUIT CIRCUITS FOR PIN ESD PROTECTION STRUCTURE

1 NC –

2 VDD A

3 D4+ A

4 D3+ A

5 D- A

6 D2+ A

7 D1+ A Circuit A

8 GND –

9 A0 B

10 TCRIT1 B

11 TCRIT2 B

12 SMBDAT B

13 SMBCLK B

14 TCRIT2 B Circuit B

(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings

only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended

Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(2) Soldering process must comply with reflow temperature profile specifications. Refer to http://www.ti.com/packaging

(3) Reflow temperature profiles are different for packages containing lead (Pb) than for those that do not.

(4) When the input voltage (VI) at any pin exceeds the power supplies (VI< GND or VI> VDD), the current at that pin must be limited to 5

mA. Parasitic components and or ESD protection circuitry are shown in the table below for the LM95214's pins.

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted) (1)(2)(3)

MIN MAX UNIT

Supply voltage –0.3 6 V

Voltage at SMBDAT, SMBCLK,

TCRIT1, TCRIT2, TCRIT3 –0.5 6 V

Voltage at other pins –0.3 VDD + 0.3 V

D−Input current ±1 mA

Input current at all other pins (4) ±5 mA

Package input current (4) 30 mA

SMBDAT, TCRIT1, TCRIT2,

TCRIT3 output sink current 10 mA

Storage temperature, Tstg –65 150 °C

(1) Human-body model, 100-pF discharged through a 1.5-kΩresistor. Machine model, 200-pF discharged directly into each pin. Charged-

device model (CDM) simulates a pin slowly acquiring charge (such as from a device sliding down the feeder in an automated

assembler) then rapidly being discharged.

(2) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.

(3) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

6.2 ESD Ratings VALUE UNIT

V(ESD) Electrostatic discharge(1) Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(2) ±2000 VCharged-device model (CDM), per JEDEC specification JESD22-C101(3) ±1000

Machine Model ±200

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6.3 Recommended Operating Conditions MIN NOM MAX UNIT

Operating temperature –40 140 °C

Supply voltage (VDD) 3 3.6 V

(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application

report.

6.4 Thermal Information

THERMAL METRIC(1) LM95214

UNITNHL (WSON)

14 PINS

RθJA Junction-to-ambient thermal resistance 38.7 °C/W

RθJC(top) Junction-to-case (top) thermal resistance 27.5 °C/W

RθJB Junction-to-board thermal resistance 16.7 °C/W

ψJT Junction-to-top characterization parameter 0.3 °C/W

ψJB Junction-to-board characterization parameter 16.6 °C/W

RθJC(bot) Junction-to-case (bottom) thermal resistance 3.2 °C/W

(1) Local temperature accuracy does not include the effects of self-heating. The rise in temperature due to self-heating is the product of the

internal power dissipation of the LM95214 and the thermal resistance. See under Recommended Operating Conditions table for the

thermal resistance to be used in the self-heating calculation.

(2) The accuracy of the LM95214CISD is ensured when using a typical MMBT3904 diode-connected transistor. For further information on

other thermal diodes see applications Diode Non-Ideality.

(3) This specification is provided only to indicate how often temperature data is updated. The LM95214 can be read at any time without

regard to conversion state (and will yield last conversion result).

(4) Quiescent current will not increase substantially with an SMBus communication.

6.5 Electrical Characteristics: Temperature-to-Digital Converter

minimum and maximum specifications are over –40°C to +125°C and V+ = +3 V to 3.6 V (unless otherwise noted); typical

specifications are at TA= TJ= 25°C and V+ = 3.3 V

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Temperature error using local diode TA= –40°C to +125°C, (1) –2 ±1 +2 °C

Temperature error using an MMBT3904

transistor remote diode(2)

TA= +25°C to +85°C

TD= +60°C to +100°C –1.1 +1.1 °C

TA= +25°C to +85°C

TD= –40°C to +125°C –1.3 +1.3 °C

TA= –40°C to +85°C

TD= –40°C to +125°C –3 +3 °C

TA= –40°C to +85°C

TD= 125°C to +140°C –3.3 +3.3 °C

Local diode measurement resolution 11 Bits

0.125 °C

Remote diode measurement resolution Digital filter off 11 Bits

0.125 °C

Digital filter on (Remote Diodes 1 and 2 only) 13 Bits

0.03125 °C

Conversion time of all temperatures at

the fastest setting(3)

All channels are enabled in default state 1100 1210 ms

1 external channel 31 34 ms

Local only 30 33 ms

Quiescent current (4) SMBus inactive, 1-Hz conversion rate, channels in

default state 570 800 µA

Shutdown 360 µA

D−Source voltage 0.4 V

Remote diode source current High level 160 230 µA

Low level 10

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Electrical Characteristics: Temperature-to-Digital Converter (continued)

minimum and maximum specifications are over –40°C to +125°C and V+ = +3 V to 3.6 V (unless otherwise noted); typical

specifications are at TA= TJ= 25°C and V+ = 3.3 V

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

Power-On reset threshold Measured on VDD input, falling edge 1.6 2.8 V

TCRIT1 pin temperature threshold Default diodes 1 and 2 only 110 °C

TCRIT2 pin temperature threshold Default all channels 85 °C

TCRIT3 pin temperature threshold Default diodes 3 and 4 only 85 °C

6.6 Logic Electrical Characteristics: Digital DC Characteristics

Unless otherwise noted all limits are specified for VDD = +3 Vdc to 3.6 Vdc, TA= TJ= +25°C.

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

SMBDAT, SMBCLK INPUTS

VIN(1) Logical 1 input voltage 2.1 V

VIN(0) Logical 0 input voltage 0.8 V

VIN(HYST) SMBDAT and SMBCLK digital

input hysteresis 400 mV

IIN(1) Logical 1 input current VIN = VDD 0.005 10 µA

IIN(0) Logical 0 input current VIN = 0 V −0.005 –10 µA

CIN Input capacitance 5 pF

A0 DIGITAL INPUT

VIH Input high voltage 0.90 ×

VDD V

VIM Input middle voltage 0.43 ×

VDD 0.57 ×

VDD V

VIL Input low voltage 0.10 ×

VDD V

IIN(1) Logical 1 input current VIN = VDD VIN = VDD –0.005 –10 µA

IIN(0) Logical 0 input current VIN = 0 V VIN = 0 V 0.005 10 µA

CIN Input capacitance 5 pF

SMBDAT, TCRIT1, TCRIT2, TCRIT3 DIGITAL OUTPUTS

IOH High level output current VOH = VDD 10 µA

VOL(SMBDAT) SMBus low level output voltage IOL = 4 mA 0.4 V

IOL = 6 mA 0.6 V

VOL(TCRIT) TCRIT1, TCRIT2, TCRIT3 low

level output voltage IOL = 6 mA 0.4 V

COUT Digital output capacitance 5 pF

VIH

VIL

SMBCL

P S

VIH

VIL

SMBDA

tBUF tHD;STA

tLOW

tHD;DAT

tHIGH

tSU;DAT tSU;STA tSU;STO

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(1) The output rise time is measured from (VIN(0)max −0.15 V) to (VIN(1)min + 0.15 V).

(2) The output fall time is measured from (VIN(1)min + 0.15 V) to (VIN(0)max −0.15 V).

6.7 Switching Characteristics: SMBus Digital

Unless otherwise noted, these specifications apply for VDD=+3.0 Vdc to +3.6 Vdc, CL(load capacitance) on output lines = 80

pF, TA= TJ= +25°C.

The switching characteristics of the LM95214 fully meet or exceed the published specifications of the SMBus version 2.0. The

following parameters are the timing relationships between SMBCLK and SMBDAT signals related to the LM95214. They

adhere to but are not necessarily the SMBus bus specifications.

PARAMETER TEST CONDITIONS MIN TYP MAX UNIT

fSMB SMBus clock frequency 10 100 kHz

tLOW SMBus clock low time from VIN(0)max to VIN(0)max 4.7 µs

25 ms

tHIGH SMBus clock high time from VIN(1)min to VIN(1)min 4.0 µs

tR,SMB SMBus rise time See (1) 1 µs

tF,SMB SMBus fall time See (2) 0.3 µs

tOF Output fall time CL= 400 pF,

IO= 3 mA(2) 250 ns

tTIMEOUT SMBDAT and SMBCLK time

low for reset of serial

interface 25 35 ms

tSU;DAT Data in setup time to

SMBCLK high 250 ns

tHD;DAT Data out stable after

SMBCLK low 300 1075 ns

tHD;STA

Start condition SMBDAT low

to SMBCLK low (Start

condition hold before the first

clock falling edge) 100 ns

tSU;STO Stop condition SMBCLK high

to SMBDAT low (Stop

condition setup) 100 ns

tSU;STA

SMBus repeated start-

condition setup time,

SMBCLK high to SMBDAT

low 0.6 µs

tBUF SMBus free time between

stop and start conditions 1.3 µs

Figure 1. SMBus Communication

Temperature (°C)

Temperature Error (°C)

-50 -30 -10 10 30 50 70 90 110 130

-0.25

0.25

0.5

0.75

1.25

D003

3.0V

3.3V

3.6V

Temperature (°C)

Temperature Error (°C)

-50 -30 -10 10 30 50 70 90 110 130

-0.25

0.25

0.5

0.75

1.25

D001

3.0V

3.3V

3.6V

Temperature (°C)

Temperature Error (°C)

-50 -30 -10 10 30 50 70 90 110 130

-0.25

0.25

0.5

0.75

1.25

D002

3.0V

3.3V

3.6V

CONVERSION TIME (ms)

100 1000 10000

0.0

0.5

1.0

1.5

2.0

2.5

3.0

AVERAGE IDD (mA)

VDD = +3.3V

TA= 25°C

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6.8 Typical Characteristics

Figure 2. Conversion Rate Effect on Average Power Supply

Current Figure 3. Thermal Diode Capacitor or PCB Leakage Current

Effect on Remote Diode Temperature Reading

Figure 4. Remote Temperature Reading Sensitivity to

Thermal Diode Filter Capacitance Figure 5. Local Temperature Error, TA= TD

Figure 6. Remote 1 Temperature Error, TA= TDFigure 7. Remote 2 Temperature Error, TA= TD

Temperature (°C)

Temperature Error (°C)

-50 -30 -10 10 30 50 70 90 110 130

-0.25

0.25

0.5

0.75

1.25

D004

3.0V

3.3V

3.6V

Temperature (°C)

Temperature Error (°C)

-50 -30 -10 10 30 50 70 90 110 130

-0.25

0.25

0.5

0.75

1.25

D005

3.0V

3.3V

3.6V

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Typical Characteristics (continued)

Figure 8. Remote 3 Temperature Error, TA= TDFigure 9. Remote 4 Temperature Error, TA= TD

3.0V-3.6V

LM95214

Local

Diode

Selector '-6Converter

11-Bit or

10-Bit Plus Sign

Remote

10-bit Plus Sign

Local

Temperature

Sensor

Circuitry

Local

Temperature

Registers

Limit,

Status

and

Mask

Registers

Remote 1

Temperature

Registers

SMBus

Interface

Remote 2

Temperature

Registers

Remote 3

Temperature

Registers

Remote 4

Temperature

Registers

Conversion

Rate Rgister

Diode

Configuration

Registers

Control Logic

D-

Remote

Diode4

Selector

D4+

Remote

Diode3

Selector

D3+

Remote

Diode2

Selector

D2+

Remote

Diode1

Selector

D1+

General

Configuration

Registers

T_CRIT

Control

Logic

SMBCLK

SMBDAT

TCRIT3

TCRIT2

TCRIT1

Remote 1

Digital Filter

Remote 1

Offset Register

Remote 2

Digital Filter

Remote 2

Offset Register

Remote 3

Status

Fault Queue

Remote 3

Offset Register

Remote 4

Status

Fault Queue

Remote 4

Offset Register

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7 Detailed Description

7.1 Overview

The LM95214 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) interface

that can monitor the temperature of four remote diodes as well as its own temperature. The LM95214 can be

used to very accurately monitor the temperature of up to four external devices such as microprocessors, graphics

processors or diode-connected 2N3904 transistor. Any device whose thermal diode can be modeled by an

MMBT3904 transistor will work well with the LM95214.

The LM95214 reports temperature in two different formats for +127.875°C/–128°C range and 0°C/255°C range.

The LM95214 has a Sigma-Delta ADC (Analog-to-Digital Converter) core which provides the first level of noise

immunity. For improved performance in a noisy environment the LM95214 includes programmable digital filters

for Remote Diode 1 and 2 temperature readings. When the digital filters are invoked the resolution for Remote

Diode 1 and 2 readings increases to 0.03125°C. For maximum flexibility and best accuracy the LM95214

includes offset registers that allow calibration of other diode types.

7.2 Functional Block Diagram

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7.3 Feature Description

The LM95214 TCRIT1, TCRIT2, and TCRIT3 active low outputs are triggered when any unmasked channel

exceeds its corresponding programmable limit and can be used to shutdown the system, to turn on the system

fans or as a microcontroller interrupt function. The current status of the TCRIT1, TCRIT2, and TCRIT3 pins can

be read back from the status registers through the SMBus interface. Two of the remote channels have two

separate limits each that control the TCRIT1 and TCRIT2 pins. The remaining two channels and the local

channel each have one limit to control both the TCRIT1 and TCRIT2 pins. The TCRIT3 pin shares the limits of

the TCRIT2 pin but allows for different masking options. All limits have a shared programmable hysteresis

Diode fault detection circuitry in the LM95214 can detect the absence or fault state of a remote diode: whether

D+ is shorted to VDD, D– or ground, or whether D+ is floating.

Remote Diode 1 and 2 temperature channels have programmable digital filters while the other two remote

temperature channels utilize a fault-queue to avoid false triggering the TCRIT pins.

The LM95214 has a three-level address pin to connect up to 3 devices to the same SMBus master. LM95214

also has programmable conversion rate register as well as a shutdown mode for power savings. One round of

conversions can be triggered in shutdown mode by writing to the one-shot register through the SMBus interface.

LM95214 can be programmed to turn off unused channels for more power savings.

The LM95214 register set has an 8-bit data structure and includes:

1. Temperature Value Registers with signed format

– Most-Significant-Byte (MSB) and Least-Significant-Byte (LSB) Local Temperature

– MSB and LSB Remote Temperature 1

– MSB and LSB Remote Temperature 2

– MSB and LSB Remote Temperature 3

– MSB and LSB Remote Temperature 4

2. Temperature Value Registers with unsigned format

– MSB and LSB Remote Temperature 1

– MSB and LSB Remote Temperature 2

– MSB and LSB Remote Temperature 3

– MSB and LSB Remote Temperature 4

3. Diode Configuration Registers

– Diode Model Select

– Remote 1 Offset

– Remote 2 Offset

– Remote 3 Offset

– Remote 4 Offset

4. General Configuration Registers

– Configuration (Standby, Fault Queue enable for Remote 3 and 4; Conversion Rate)

– Channel Conversion Enable

– Filter Setting for Remote 1 and 2

– 1-Shot

5. Status Registers

– Main Status Register (Busy bit, Not Ready, Status Register 1 to 4 Flags)

– Status 1 (diode fault)

– Status 2 (TCRIT1)

– Status 3 (TCRIT2)

– Status 4 (TCRIT3)

6. Mask Registers

– TCRIT1 Mask

– TCRIT2 Mask

CONVERSION TIME (ms)

100 1000 10000

0.0

0.5

1.0

1.5

2.0

2.5

3.0

AVERAGE IDD (mA)

VDD = +3.3V

TA= 25°C

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Feature Description (continued)

– TCRIT3 Mask

7. Limit Registers

– Local Tcrit Limit

– Remote 1 Tcrit-1 Limit

– Remote 2 Tcrit-1 Limit

– Remote 3 Tcrit Limit

– Remote 4 Tcrit Limit

– Remote 1 Tcrit-2 and Tcrit-3 Limit

– Remote 2 Tcrit-2 and Tcrit-3 Limit

– Common Tcrit Hysteresis

8. Manufacturer ID Register

9. Revision ID Register

7.3.1 Conversion Sequence

The LM95214 takes approximately 190 ms to convert the Local Temperature, Remote Temperatures 1 through

4, and to update all of its registers. These conversions for each thermal diode are addressed in a round robin

sequence. Only during the conversion process the busy bit (D7) in Status register (02h) is high. The conversion

rate may be modified by the Conversion Rate bits found in the Configuration Register (03h). When the

conversion rate is modified a delay is inserted between each round of conversions, the actual time for each

round remains at 190 ms (typical all channels enabled). The time a round takes depends on the number of

channels that are on. Different conversion rates will cause the LM95214 to draw different amounts of average

supply current as shown in Figure 10. This curve assumes all the channels are on. If channels are turned off the

average current will drop because the round robin time will decrease and the shutdown time will increase during

each conversion interval.

Figure 10. Conversion Rate Effect on Power Supply Current

7.3.2 Power-On-Default States

The LM95214 always powers up to these known default states. The LM95214 remains in these states until after

the first conversion.

1. All Temperature readings set to 0°C until the end of the first conversion

2. Remote offset for all channels 0°C

3. Configuration: Active converting, Fault Queue enabled for Remote 3 and 4

4. Continuous conversion with all channels enabled, time = 1 s

5. Enhanced digital filter enabled for Remote 1 and 2

6. Status Registers depends on state of thermal diode inputs

7. Local and Remote Temperature Limits for TCRIT1, TCRIT2 and TCRIT3 outputs:

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Feature Description (continued)

Table 2. Temperature Channel limits

OUTPUT PIN TEMPERATURE CHANNEL LIMIT

REMOTE 4

(°C) REMOTE 3

(°C) REMOTE 2

(°C) REMOTE 1

(°C) LOCAL

(°C)

TCRIT1 Masked,

85 Masked,

85 110 110 Masked,

TCRIT2 85 85 85 85 85

TCRIT3 85 85 Masked,

85 Masked,

8. Manufacturers ID set to 01h

9. Revision ID set to 79h

7.3.3 SMBus Interface

The LM95214 operates as a slave on the SMBus, so the SMBCLK line is an input and the SMBDAT line is

bidirectional. The LM95214 never drives the SMBCLK line and it does not support clock stretching. According to

SMBus specifications, the LM95214 has a 7-bit slave address. Three SMBus device address can be selected by

connecting A0 (pin 6) to either Low, Mid-Supply, or High voltages. The LM95214 has the following SMBus slave

address:

Table 3. SMBus Slave Addresses

A0 PIN STATE SMBus DEVICE ADDRESS A[6:0]

HEX BINARY

Low 18h 001 1000

Mid-Supply 4Dh 100 1101

High 4Eh 100 1110

7.3.4 Temperature Conversion Sequence

Each of the 5 temperature channels of LM95214 can be turned OFF independent from each other through the

Channel Enable Register. Turning off unused channels will increase the conversion speed in the fastest

conversion speed mode. If the slower conversion speed settings are used, disabling unused channels will reduce

the average power consumption of LM95214.

7.3.4.1 Digital Filter

To suppress erroneous remote temperature readings due to noise as well as increase the resolution of the

temperature, the LM95214 incorporates a digital filter for Remote 1 and 2 Temperature Channels. When a filter is

enabled the filtered readings are used for the TCRIT comparisons. There are two possible digital filter settings

that are enabled through the Filter Setting Register at register address 0Fh. The filter for each channel can be

set according to the following table:

Table 4. Digital Filter Settings

R1F[1:0] OR R2F[1:0] FILTER SETTING

0 0 No Filter

0 1 Filter (equivalent to Level 2 filter of the LM86/LM89)

1 0 Reserved

1 1 Enhanced Filter (Filter with transient noise clipping)

0 50 100 150 200

SAMPLE NUMBER

TEMPERATURE (°C)

LM95214 with

Filter On

LM95214 with

Filter Off

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Figure 11,Figure 12, and Figure 13 describe the filter output in response to a step input and an impulse input.

Figure 11. Seventeen and Fifty Degree Step Response Figure 12. Impulse Response With Input Transients Less

Than 4°C

Figure 13. Impulse Response With Input Transients

Greater Than 4°C

Figure 14. Digital Filter Response in a Typical Intel

Processor on a 65 nm or 90 nm Process. The Filter Curves

Were Purposely Offset for Clarity.

Figure 14 shows the filter in use in a typical system. Note that the two curves have been purposely offset for

clarity. Inserting the filter does not induce an offset as shown.

7.3.5 Fault Queue

To suppress erroneous TCRIT1,TCRIT2 and TCRIT3 triggering the LM95214 incorporates a Fault Queue for the

unfiltered remote channels 3 and 4. The Fault Queue acts to ensure the remote temperature measurement of

these channels is genuinely beyond the corresponding Tcrit limit by not triggering until three consecutive out of

limit measurements have been made, see Figure 15 for an example. The Fault Queue defaults on upon power-

up. The fault queue for channels 3 and 4 can be turned ON or OFF through bits 0 and 1 of the Configuration

temperature is above the Tcrit limit for 3 consecutive conversions and the corresponding mask bit is 0 in the

TCRIT Mask registers. Similarly the temperature needs to be below the Tcrit limit minus the hysteresis value for

three consecutive conversions for the TCRIT1, TCRIT2 and TCRIT3 pins to deactivate.

Remote 4

Tcrit Limit

Value

Status 4

R4T3 Bit

Remote 4 Temperature Readings

SAMPLE NUMBER

n+1

n+2

n+3

n+4

n+5

n+6

n+7

n+8

n+9

n+10

n+11

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Figure 15. Fault Queue Response Diagram (With 0°C Hysteresis)

7.3.6 Temperature Data Format

Temperature data can only be read from the Local and Remote Temperature value registers. The data format for

all temperature values is left justified 16-bit word available in two 8-bit registers. Unused bits will always report 0.

All temperature data is clamped and will not roll over when a temperature exceeds full-scale value.

Remote temperature data for all channels can be represented by an 11-bit, two's complement word or unsigned

binary word with an LSb (Least Significant Bit) equal to 0.125°C.

Table 5. 11-Bit, 2's Complement (10-Bit Plus Sign)

TEMPERATURE DIGITAL OUTPUT

BINARY HEX

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.125°C 0000 0000 0010 0000 0020h

0°C 0000 0000 0000 0000 0000h

−0.125°C 1111 1111 1110 0000 FFE0h

−1°C 1111 1111 0000 0000 FF00h

−25°C 1110 0111 0000 0000 E700h

−55°C 1100 1001 0000 0000 C900h

Table 6. 11-Bit Unsigned Binary

TEMPERATURE DIGITAL OUTPUT

BINARY HEX

+255.875°C 1111 1111 1110 0000 FFE0h

+255°C 1111 1111 0000 0000 FF00h

+201°C 1100 1001 0000 0000 C900h

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.125°C 0000 0000 0010 0000 0020h

0°C 0000 0000 0000 0000 0000h

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When the digital filter is enabled on Remote 1 and 2 channels temperature data is represented by a 13-bit

unsigned binary or 12-bit plus sign (two's complement) word with an LSb equal to 0.03125°C.

Table 7. 13-Bit, 2's Complement (12-Bit Plus Sign)

TEMPERATURE DIGITAL OUTPUT

BINARY HEX

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.03125°C 0000 0000 0000 1000 0008h

0°C 0000 0000 0000 0000 0000h

−0.03125°C 1111 1111 1111 1000 FFF8h

−1°C 1111 1111 0000 0000 FF00h

−25°C 1110 0111 0000 0000 E700h

−55°C 1100 1001 0000 0000 C900h

Table 8. 13-Bit, Unsigned Binary

TEMPERATURE DIGITAL OUTPUT

BINARY HEX

+255.875°C 1111 1111 1110 0000 FFE0h

+255°C 1111 1111 0000 0000 FF00h

+201°C 1100 1001 0000 0000 C900h

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.03125°C 0000 0000 0000 1000 0008h

0°C 0000 0000 0000 0000 0000h

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Local Temperature data is only represented by an 11-bit, two's complement, word with an LSb equal to 0.125°C.

Table 9. 11-Bit, 2's Complement (10-Bit Plus Sign)

TEMPERATURE DIGITAL OUTPUT

BINARY HEX

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.125°C 0000 0000 0010 0000 0020h

0°C 0000 0000 0000 0000 0000h

−0.125°C 1111 1111 1110 0000 FFE0h

−1°C 1111 1111 0000 0000 FF00h

−25°C 1110 0111 0000 0000 E700h

−55°C 1100 1001 0000 0000 C900h

7.3.7 SMBDAT Open-Drain Output

The SMBDAT output is an open-drain output and does not have internal pullups. A high level will not be

observed on this pin until pullup current is provided by some external source, typically a pullup resistor. Choice of

resistor value depends on many system factors but, in general, the pullup resistor must be as large as possible

without effecting the SMBus desired data rate. This will minimize any internal temperature reading errors due to

internal heating of the LM95214. The maximum resistance of the pullup to provide a 2.1-V high level, based on

LM95214 specification for High Level Output Current with the supply voltage at 3 V, is 82 kΩ(5%) or 88.7 kΩ

(1%).

7.3.8 TCRIT1, TCRIT2, and TCRIT3 Outputs

The LM95214's TCRIT pins are active-low open-drain outputs and do not include internal pullup resistors. A high

level will not be observed on these pins until pullup current is provided by some external source, typically a

pullup resistor. Choice of resistor value depends on many system factors but, in general, the pullup resistor must

be as large as possible without effecting the performance of the device receiving the signal. This will minimize

any internal temperature reading errors due to internal heating of the LM95214. The maximum resistance of the

pullup to provide a 2.1-V high level, based on LM95214 specification for High Level Output Current with the

supply voltage at 3 V, is 82 kΩ(5%) or 88.7 kΩ(1%). The three TCRIT pins can each sink 6 mA of current and

still ensured a Logic Low output voltage of 0.4 V. If all three pins are set at maximum current this will cause a

power dissipation of 7.2 mW. This power dissipation combined with a thermal resistance of 77.8°C/W will cause

the LM95214's junction temperature to rise approximately 0.6°C and thus cause the Local temperature reading to

shift. This can only be cancelled out if the environment that the LM95214 is enclosed in has stable and controlled

air flow over the LM95214, as airflow can cause the thermal resistance to change dramatically.

7.3.9 TCRIT Limits and TCRIT Outputs

Figure 16 describes a simplified diagram of the temperature comparison and status register logic. Figure 17,

Figure 18, and Figure 19 describe simplified logic diagrams of the circuitry associated with the status registers,

mask registers, and the TCRIT output pins.

Status 2

(TCRIT1)

R4T1

R3T1

R2T1

R1T1

LT1

Common Tcrit Hysteresis

Remote Temp 4

Remote 4 Tcrit Limit

AB

AtB

Remote Temp 3

Remote 3 Tcrit Limit

AB

AtB

Remote Temp 2

Remote 2 Tcrit-1 Limit

AB

AtB

Remote 1 Tcrit2 & Tcrit-3

Limit

AB

AtB

Local Temp

Local Tcrit Limit

AB

AtB

Status 4

(TCRIT3)

R4T3

R3T3

R2T3

R1T3

LT3

Status 3

(TCRIT2)

R4T2

R3T2

R2T2

R1T2

LT2

Remote 2 Tcrit-2 & Tcrit-3

Limit

AB

AtB

Remote Temp 1

Remote 1 Tcrit-1 Limit

AB

AtB

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Figure 16. Temperature Comparison Logic and Status Register Simplified Diagram

TCRIT3

Status 4

(TCRIT3)

R4T3

R3T3

R2T3

R1T3

LT3

TCRIT3

Mask

R4TM

R3TM

R2T2M

R1T2M

LTM

Status 1 (Diode

Fault)

R4DO

R4DS

R3DO

R3DS

R2DO

R2DS

R1DO

R1DS

TCRIT1

Status 1

(Diode Fault)

R4DO

R4DS

R3DO

R3DS

R2DO

R2DS

R1DO

R1DS

Status 2

(TCRIT1)

R4T1

R3T1

R2T1

R1T1

LT1

TCRIT1

Mask

R4TM

R3TM

R2T1M

R1T1M

LTM

TCRIT2

Status 3

(TCRIT2)

R4T2

R3T2

R2T2

R1T2

LT2

TCRIT2

Mask

R4TM

R3TM

R2T2M

R1T2M

LTM

Status 1

(Diode Fault)

R4DO

R4DS

R3DO

R3DS

R2DO

R2DS

R1DO

R1DS

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Figure 17. TCRIT1 Mask Register, Status Register 1 and 2,

and TCRIT1 Output Logic Diagram Figure 18. TCRIT2 Mask Register, Status Register 1 and 3,

and TCRIT2 Output Logic Diagram

Figure 19. TCRIT3 Mask Register, Status Register 1 and 4, and TCRIT3 Output Logic Diagram

If enabled, local temperature is compared to the user programmable Local Tcrit Limit Register (Default Value =

85°C). The result of this comparison is stored in Status Register 2, Status Register 3 and Status Register 4 (see

Figure 16). The comparison result can trigger TCRIT1 pin, TCRIT2 pin or TCRIT3 pin depending on the settings

in the TCRIT1 Mask, TCRIT2 Mask and TCRIT3 Mask Registers (see Figure 17,Figure 18, and Figure 19). The

comparison result can also be read back from the Status Register 2, Status Register 3 and Status Register 4.

T_CRITn

Output Pin

Local Tcrit Limit

Local

Temperature

Status bit LTn

Local Tcrit Limit -

Common Hysteresis

Common

Hysteresis

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If enabled, remote temperature 1 is compared to the user programmable Remote 1 Tcrit-1 Limit Register (Default

Value 110°C) and Remote 1 Tcrit-2 Limit Register (Default Value = 85°C). The result of this comparison is stored

in Status Register 2, Status Register 3 and Status Register 4 (see Figure 16). The comparison result can trigger

TCRIT1 pin, TCRIT2 pin or TCRIT3 pin depending on the settings in the TCRIT1 Mask, TCRIT2 Mask and

TCRIT3 Mask Registers (see Figure 17,Figure 18, and Figure 19). The comparison result can also be read back

from the Status Register 2, Status Register 3 and Status Register 4. The remote temperature 2 operates in a

similar manner to remote temperature 1 using its associated user programmable limit registers: Remote 2 Tcrit-1

Limit Register (Default Value 110°C) and Remote 2 Tcrit-2 Limit Register (Default Value = 85°C). When enabled,

the remote temperature 3 is compared to the user programmable Remote 3 Tcrit Limit Register (Default Value

85°C). The comparison result can trigger TCRIT1 pin, TCRIT2 pin or TCRIT3 pin depending on the settings in

the TCRIT1 Mask, TCRIT2 Mask and TCRIT3 Mask Registers. The comparison result can also be read back

from the Status Register 2, Status Register 3 and Status Register 4. The remote temperature 4 operates in a

similar manner to remote temperature 3 using its associated user programmable limit register: Remote 4 Tcrit

Limit Register (Default Value 85°C).

Table 10. Limit Assignments for Each TCRIT Output Pin:

TCRIT1 TCRIT2 TCRIT3

Remote 4 Remote 4

Tcrit Limit Remote 4

Tcrit Limit

Remote 3 Remote 3

Tcrit Limit Remote 3

Tcrit Limit

Remote 2 Remote 2

Tcrit-1 Limit Remote 2

Tcrit-2 Limit Remote 2

Tcrit-2 Limit

Remote 1 Remote 1

Tcrit-1 Limit Remote 1

Tcrit-2 Limit Remote 1

Tcrit-2 Limit

Local Local

Tcrit Limit Local

Tcrit Limit

Figure 20. TCRIT Response Diagram (Masking Options Not Included)

The TCRIT response diagram of Figure 20 shows the local temperature interaction with the Tcrit limit and

hysteresis value. As can be seen in the diagram when the local temperature exceeds the Tcrit limit register value

the LTn Status bit is set and the T_CRITn output(s) is/are activated. The Status bit(s) and outputs are not

deactivated until the temperature goes below the value calculated by subtracting the Common Hysteresis value

programmed from the limit. This diagram mainly shows an example function of the hysteresis and is not meant to

show complete function of the possible settings and options of all the TCRIT outputs and limit values.

7.4 Device Functional Modes

7.4.1 Diode Fault Detection

The LM95214 is equipped with operational circuitry designed to detect fault conditions concerning the remote

diodes. In the event that the D+ pin is detected as shorted to GND, D−, VDD or D+ is floating, the Remote

Temperature reading is –128.000°C if signed format is selected and 0°C if unsigned format is selected. In

addition, the appropriate status register bits RD1M or RD2M (D1 or D0) are set.

D7 D6 D5 D4 D3 D2 D1 D0

1 9 1 9

Ack

LM95214

Start by

Master

R/W

Frame 1

Serial Bus Address Byte Frame 2

Command Byte

Ack by

LM95214

SMBCLK

SMBDAT A5 A3 A2 A0

A6 A4 A1 Stop

Master

D7 D6 D5 D4 D3 D2 D1 D0

1 9 1 9

Ack

LM95214

Start by

Master

R/W

Frame 1

Serial Bus Address Byte Frame 2

Command Byte

Ack

LM95214

D7 D6 D5 D4 D3 D2 D1 D0

1 9

Frame 3

Data Byte

Ack by

LM95214Stop

Master

SMBCLK

SMBDAT

SMBCLK

(Continued)

SMBDAT

(Continued)

A5 A3 A2 A0A6 A4 A1

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Device Functional Modes (continued)

7.4.2 Communicating With the LM95214

The data registers in the LM95214 are selected by the Command Register. At power-up the Command Register

is set to 00, the location for the Read Local Temperature Register. The Command Register latches the last

location it was set to. Each data register in the LM95214 falls into one of three types of user accessibility:

1. Read only

2. Write only

3. Write/Read same address

AWrite to the LM95214 will always include the address byte and the command byte. A write to any register

requires one data byte.

Reading the LM95214 can take place either of two ways:

1. If the location latched in the Command Register is correct (most of the time it is expected that the Command

read from the LM95214), then the read can simply consist of an address byte, followed by retrieving the data

byte.

2. If the Command Register needs to be set, then an address byte, command byte, repeat start, and another

address byte will accomplish a read.

The data byte has the most significant bit first. At the end of a read, the LM95214 can accept either acknowledge

or No Acknowledge from the Master (No Acknowledge is typically used as a signal for the slave that the Master

has read its last byte). It takes the LM95214 190 ms (typical, all channels enabled) to measure the temperature

of the remote diodes and internal diode. When retrieving all 11 bits from a previous remote diode temperature

measurement, the master must insure that all 11 bits are from the same temperature conversion. This may be

achieved by reading the MSB register first. The LSB will be locked after the MSB is read. The LSB will be

unlocked after being read. If the user reads MSBs consecutively, each time the MSB is read, the LSB associated

with that temperature will be locked in and override the previous LSB value locked-in.

Figure 21. Serial Bus Write to the Internal Command Register Followed by a the Data Byte

Figure 22. Serial Bus Write to the Internal Command Register

D7 D6 D5 D4 D3 D2 D1 D0

1 9 1 9

Ack

LM95214

Start by

Master Repeat

Start by

Master

R/W

Frame 1

Serial Bus Address Byte Frame 2

Command Byte

Ack

LM95214

D7 D6 D5 D4 D3 D2 D1 D0

1 9 1 9

Ack

LM95214

R/W

Frame 3

Serial Bus Address Byte Frame 4

Data Byte from the LM95214

No Ack

Master

Stop

Master

SMBCLK

SMBDAT

SMBCLK

(Continued)

SMBDAT

(Continued)

A5 A3 A2 A0

A6 A4 A1

A5 A3 A2 A0

A6 A4 A1

D7 D6 D5 D4 D3 D2 D1 D0

1 9 1 9

Ack

LM95214

Start by

Master

R/W

Frame 1

Serial Bus Address Byte Frame 2

Data Byte from the LM95214

NoAck

Master

SMBCLK

SMBDAT Stop

Master

A5 A3 A2 A0

A6 A4 A1

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Device Functional Modes (continued)

Figure 23. Serial Bus Read From a Register With the Internal Command Register Preset to Desired Value

Figure 24. Serial Bus Write Followed by a Repeat Start and Immediate Read

7.4.3 Serial Interface Reset

In the event that the SMBus Master is RESET while the LM95214 is transmitting on the SMBDAT line, the

LM95214 must be returned to a known state in the communication protocol. This may be done in one of two

ways:

1. When SMBDAT is LOW, the LM95214 SMBus state machine resets to the SMBus idle state if either

SMBDAT or SMBCLK are held low for more than 35ms (tTIMEOUT). Note that according to SMBus

specification 2.0 all devices are to timeout when either the SMBCLK or SMBDAT lines are held low for 25 to

35 ms. Therefore, to insure a timeout of all devices on the bus the SMBCLK or SMBDAT lines must be held

low for at least 35 ms.

2. When SMBDAT is HIGH, have the master initiate an SMBus start. The LM95214 will respond properly to an

SMBus start condition at any point during the communication. After the start the LM95214 will expect an

SMBus Address byte.

7.4.4 One-Shot Conversion

The One-Shot register is used to initiate a round of conversions and comparisons when the device is in standby

mode, after which the device returns to standby. This is not a data register and it is the write operation that

causes the one-shot conversion. The data written to this address is irrelevant and is not stored. A zero will

always be read from this register. All the channels that are enabled in the Channel Enable Register will be

converted once and the TCRIT1, TCRIT2, and TCRIT3 pins will reflect the comparison results based on this

round of conversion results of the channels that are not masked.

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7.5 Register Maps

7.5.1 LM95214 Registers

Command register selects which registers will be read from or written to. Data for this register must be

transmitted during the Command Byte of the SMBus write communication.

P7 P6 P5 P4 P3 P2 P1 P0

Command Byte

P0-P7: Command

Table 11. Register Summary

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Local Temp MSB 0x10 RO SIGN 64 32 16 8 4 2 1 –

Local Temp LSB 0x20 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 1 MSB – Signed 0x11 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Signed,

Digital Filter Off 0x21 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 1 LSB – Signed,

Digital Filter On 1/16 1/32

Remote Temp 2 MSB – Signed 0x12 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Signed,

Digital Filter Off 0x22 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 2 LSB – Signed,

Digital Filter On 1/16 1/32

Remote Temp 3 MSB – Signed 0x13 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 3 LSB – Signed 0x23 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 4 MSB – Signed 0x14 RO SIGN 64 32 16 8 4 2 0 –

Remote Temp 4 LSB – Signed 0x24 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 1 MSB – Unsigned 0x19 RO 128 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Unsigned,

Digital Filter Off 0x29 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 1 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote Temp 2 MSB – Unsigned 0x1A RO 128 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Unsigned,

Digital Filter Off 0x2A RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 2 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote Temp 3 MSB – Unsigned 0x1B RO 128 64 32 16 8 4 2 1 –

Remote Temp 3 LSB – Unsigned 0x2B RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 4 MSB – Unsigned 0x1C RO 128 64 32 16 8 4 2 1 –

Remote Temp 4 LSB – Unsigned 0x2C RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote 1 Offset 0x31 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 2 Offset 0x32 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 3 Offset 0x33 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 4 Offset 0x34 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Configuration 0x03 R/W – STBY – – – – R4QE R3QE 0x03

Conversion Rate 0x04 R/W – – – – – – CR1 CR0 0x02

Channel Conversion Enable 0x05 R/W – – – R4CE R3CE R2CE R1CE LCE 0x1F

Filter Setting 0x06 R/W – – – – R2F1 R2F0 R1F1 R1F0 0x0F

1-shot 0x0F WO – – – – – – – – –

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Table 11. Register Summary (continued)

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Common Status Register 0x02 RO BUSY NR – – SR4F SR3F SR2F SR1F 0x00

Status 1 (Diode Fault) 0x07 RO R4DO R4DS R3DO R3DS R2DO R2DS R1DO R1DS –

Status 2 (TCRIT1) 0x08 RO – – – R4T1 R3T1 R2T1 R1T1 LT1 –

Status 3 (TCRIT2) 0x09 RO – – – R4T2 R3T2 R2T2 R1T2 LT2 –

Status 4 (TCRIT3) 0x0A RO – – – R4T3 R3T3 R2T3 R1T3 LT3 –

TCRIT1 Mask 0x0C R/W – – – R4TM R3TM R2T1M R1T1M LTM 0x19

TCRIT2 Mask 0x0D R/W – – – R4TM R3TM R2T2M R1T2M LTM 0x00

TCRIT3 Mask 0x0E R/W – – – R4TM R3TM R2T2M R1T2M LTM 0x07

Local Tcrit Limit 0x40 R/W 0 64 32 16 8 4 2 1 0x55

Remote 1 Tcrit-1 Limit 0x41 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 2 Tcrit-1 Limit 0x42 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 3 Tcrit Limit 0x43 R/W 128 64 32 16 8 4 2 1 0x55

Remote 4 Tcrit Limit 0x44 R/W 128 64 32 16 8 4 2 1 0x55

Remote 1 Tcrit-2 and Tcrit-3 Limit 0x49 R/W 128 64 32 16 8 4 2 1 0x55

Remote 2 Tcrit-2 and Tcrit-3 Limit 0x4A R/W 128 64 32 16 8 4 2 1 0x55

Common Tcrit Hysteresis 0x5A R/W 0 0 0 16 8 4 2 1 0x0A

Manufacturer ID 0xFE RO 0 0 0 0 0 0 0 1 0x01

Revision ID 0xFF RO 0 1 1 1 1 0 0 1 0x79

7.5.1.1 Value Registers

For data synchronization purposes, the MSB register must be read first if the user wants to read both MSB and

LSB registers. The LSB will be locked after the MSB is read. The LSB will be unlocked after being read. If the

user reads MSBs consecutively, each time the MSB is read, the LSB associated with that temperature will be

locked in and override the previous LSB value locked-in

7.5.1.1.1 Local Value Registers

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Local Temp MSB 0x10 RO SIGN 64 32 16 8 4 2 1 –

Local Temp LSB 0x20 RO 1/2 1/4 1/8 0 0 0 0 0 –

Bit(s) Bit Name Read/Write Description

7 SIGN RO Sign bit

The Local temperature MSB value register

range is +127°C to −128°C. The value

programmed in this register is used to

determine a local temperature error event.

6 64 RO bit weight 64°C

5 32 RO bit weight 32°C

4 16 RO bit weight 16°C

3 8 RO bit weight 8°C

2 4 RO bit weight 4°C

1 2 RO bit weight 2°C

0 1 RO bit weight 1°C

Bit(s) Bit Name Read/Write Description

7 1/2 RO bit weight 1/2°C (0.5°C) The Local Limit register range is 0°C to

127°C. The value programmed in this

temperature error event.

6 1/4 RO bit weight 1/4°C (0.25°C)

5 1/8 RO bit weight 1/8°C (0.125°C)

4-0 0 RO Reserved – will report 0 when read.

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7.5.1.1.2 Remote Temperature Value Registers With Signed Format

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote Temp 1 MSB – Signed 0x11 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Signed, Digital

Filter Off 0x21 RO 1/2 1/8 0 0 0 0 0 0 –

Remote Temp 1 LSB – Signed, Digital

Filter On 1/16 1/32

Remote Temp 2 MSB – Signed 0x12 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Signed, Digital

Filter Off 0x22 RO 1/2 1/8 0 0 0 0 0 0 –

Remote Temp 2 LSB – Signed, Digital

Filter On 1/16 1/32

Remote Temp 3 MSB – Signed 0x13 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 3 LSB – Signed 0x23 RO 1/2 1/8 0 0 0 0 0 0 –

Remote Temp 4 MSB – Signed 0x14 RO SIGN 64 32 16 8 4 2 0 –

Remote Temp 4 LSB – Signed 0x24 RO 1/2 1/8 0 0 0 0 0 0 –

The Local temperature MSB value register range is +127°C to −128°C. The value programmed in this register is

used to determine a local temperature error event.

Bit(s) Bit Name Read/Write Description

7 SIGN RO Sign bit

6 64 RO bit weight 64°C

5 32 RO bit weight 32°C

4 16 RO bit weight 16°C

3 8 RO bit weight 8°C

2 4 RO bit weight 4°C

1 2 RO bit weight 2°C

0 1 RO bit weight 1°C

Bit(s) Bit Name Read/Write Description

7 1/2 RO bit weight 1/2°C (0.5°C)

6 1/4 RO bit weight 1/4°C (0.25°C)

5 1/8 RO bit weight 1/8°C (0.125°C)

4 0 or 1/16 RO When the digital filter is disabled this bit will always read 0.

When the digital filter is enabled this bit will report 1/16°C (0.0625°C) bit state.

3 0 or 1/32 RO When the digital filter is disabled this bit will always read 0.

When the digital filter is enabled this bit will report 1/32°C (0.03125°C) bit state.

2-0 0 RO Reserved – will report 0 when read.

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7.5.1.1.3 Remote Temperature Value Registers With Unsigned Format

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote Temp 1 MSB – Unsigned 0x19 RO 128 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Unsigned,

Digital Filter Off 0x29 RO 1/2 1/8 0 0 0 0 0 0 –

Remote Temp 1 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote Temp 2 MSB – Unsigned 0x1A RO 128 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Unsigned,

Digital Filter Off 0x2A RO 1/2 1/8 0 0 0 0 0 0 –

Remote Temp 2 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote Temp 3 MSB – Unsigned 0x1B RO 128 64 32 16 8 4 2 1 –

Remote Temp 3 LSB – Unsigned 0x2B RO 1/2 1/8 0 0 0 0 0 0 –

Remote Temp 4 MSB – Unsigned 0x1C RO 128 64 32 16 8 4 2 1 –

Remote Temp 4 LSB – Unsigned 0x2C RO 1/2 1/8 0 0 0 0 0 0 –

Bit(s) Bit Name Read/Write Description

7 SIGN RO bit weight 128°C

6 64 RO bit weight 64°C

5 32 RO bit weight 32°C

4 16 RO bit weight 16°C

3 8 RO bit weight 8°C

2 4 RO bit weight 4°C

1 2 RO bit weight 2°C

0 1 RO bit weight 1°C

Bit(s) Bit Name Read/Write Description

7 1/2 RO bit weight 1/2°C (0.5°C)

6 1/4 RO bit weight 1/4°C (0.25°C)

5 1/8 RO bit weight 1/8°C (0.125°C)

4 0 or 1/16 RO When the digital filter is disabled this bit will always read 0.

When the digital filter is enabled this bit will report 1/16°C (0.0625°C) bit state.

3 0 or 1/32 RO When the digital filter is disabled this bit will always read 0.

When the digital filter is enabled this bit will report 1/32°C (0.03125°C) bit state.

2-0 0 RO Reserved – will report 0 when read.

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7.5.1.2 Diode Configuration Register

7.5.1.2.1 Remote 1-4 Offset

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote 1 Offset 0x31 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 2 Offset 0x32 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 3 Offset 0x33 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 4 Offset 0x34 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Bit(s) Bit Name Read/Write Description

7 SIGN R/W Sign bit All registers have 2’s complement format.

The offset range for each remote is

+63.5°C/−64°C. The value programmed in

this register is directly added to the actual

reading of the ADC and the modified number

is reported in the remote value registers.

6 32 R/W bit weight 32°C

5 16 R/W bit weight 16°C

4 8 R/W bit weight 8°C

3 4 R/W bit weight 4°C

2 2 R/W bit weight 2°C

1 1 R/W bit weight 1°C

0 1/2 R/W bit weight 1/2°C (0.5°C)

7.5.1.3 Configuration Registers

7.5.1.3.1 Main Configuration Register

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Configuration 0×03 R/W – STBY – – – – R4QE R3QE 0×03

Bit(s) Bit Name Read/Write Description

7 – RO Reserved will report 0 when read.

6 STBY R/W Software Standby

1 – standby (when in this mode one conversion sequence can be initiated by writing to the

one-shot register)

0 – active/converting

5–2 – RO Reserved – will report 0 when read.

1 R4QE R/W Fault queue enable for Remote 4

1– Fault queue enabled

0– Fault queue disabled

0 R3QE R/W Fault queue enable for Remote 3

1– Fault queue enabled

0– Fault queue disabled

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7.5.1.3.2 Conversion Rate Register

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Conversion Rate 0×04 R/W – – – – – – CR1 CR0 0×02

Bit(s) Bit Name Read/Write Description

7-2 – RO Reserved – will report 0 when read.

1-0 CR[1:0] R/W Conversion rate control bits modify the time interval for conversion of the channels enabled.

The channels enabled are converted sequentially then standby mode enabled for the

remainder of the time interval.

CR[1:0] Conversion Rate

00 continuous (30 ms to 143 ms)

01 0.364 s

10 1s

11 2.5 s

7.5.1.3.3 Channel Conversion Enable

When a conversion is disabled for a particular channel it is skipped. The continuous conversion rate is effected

all other conversion rates are not effected as extra standby time is inserted to compensate. See Conversion Rate

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Channel Conversion Enable 0×05 R/W – – – R4CE R3CE R2CE R1CE LCE 0×1F

Bit(s) Bit Name Read/Write Description

7–5 – RO Reserved – will report 0 when read.

4 R4CE R/W Remote 4 Temperature Conversion Enable

1– Remote 4 temp conversion enabled

0– Remote 4 temp conversion disabled

3 R3CE R/W Remote 3 Temperature Conversion Enable

1– Remote 3 temp conversion enabled

0– Remote 3 temp conversion disabled

2 R2CE R/W Remote 2 Temperature Conversion Enable

1– Remote 2 temp conversion enabled

0– Remote 2 temp conversion disabled

1 R1CE R/W Remote 1 Temperature Conversion Enable

1– Remote 1 temp conversion enabled

0– Remote 1 temp conversion disabled

0 LCE R/W Local Temperature Conversion Enable

1– Local temp conversion enabled

0– Local temp conversion disabled

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7.5.1.3.4 Filter Setting

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Filter Setting 0x06 R/W – – – – R2F1 R2F0 R1F1 R1F0 0x0F

Bit(s) Bit Name Read/Write Description

7–4 – RO Reserved – will report 0 when read.

3–2 R2F[1:0] R/W Remote Channel 2 Filter Enable Bits

R2F[1:0] Digital Filter State

00 disable all digital filtering

01 enable basic filter

10 reserved (do not use)

11 enable enhanced filter

1–0 R1F[1:0] R/W Remote Channel 1 Filter Enable

R1F[1:0] Filter State

00 disable all digital filtering

01 enable basic filter

10 reserved (do not use)

11 enable enhanced filter

7.5.1.3.5 1-Shot

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

1-Shot 0×0F WO – – – – – – – – –

Bit(s) Bit Name Read/Write Description

7–0 - WO Writing to this register activates one conversion for all the enabled channels if the

chip is in standby mode (that is,. standby bit = 1). The actual data written does

not matter and is not stored.

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7.5.1.4 Status Registers

7.5.1.4.1 Common Status Register

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Common Status Register 0×02 RO BUSY NR – – SR4F SR3F SR2F SR1F 0×00

Bit(s) Bit Name Read/Write Description

7 BUSY RO Busy bit (device converting)

6 NR RO Not Ready bit (30 ms), indicates power up initialization sequence is in progress

5–4 – RO Reserved – will report 0 when read.

3 SR4F RO Status Register 4 Flag:

1 – indicates that Status Register 4 has at least one bit set

0 – indicates that all of Status Register 4 bits are cleared

2 SR3F RO Status Register 3 Flag:

1 – indicates that Status Register 3 has at least one bit set

0 – indicates that all of Status Register 3 bits are cleared

1 SR2F RO Status Register 2 Flag:

1 – indicates that Status Register 2 has at least one bit set

0 – indicates that all of Status Register 2 bits are cleared

0 SR1F RO Status Register 1 Flag:

1 – indicates that Status Register 1 has at least one bit set

0 – indicates that all of Status Register 1 bits are cleared

7.5.1.4.2 Status 1 Register (Diode Fault)

Status fault bits for open or shorted diode (that is,. Short Fault: D+ shorted to Ground or D-; Open Fault: D+

shorted to VDD, or floating). During fault conditions the temperature reading is 0 °C if unsigned value registers are

read or –128.000 °C if signed value registers are read.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 1 (Diode Fault) 0×07 RO R4DO R4DS R3DO R3DS R2DO R2DS R1DO R1DS –

Bit(s) Bit Name Read/Write Description

7 R4DO RO Remote 4 diode open fault status:

1 – indicates that remote 4 diode has an "open" fault

0 – indicates that remote 4 diode does not have an "open" fault

6 R4DS RO Remote 4 diode short fault status:

1 – indicates that remote 4 diode has a "short" fault

0 – indicates that remote 4 diode does not have a "short" fault

5 R3DO RO Remote 3 diode open fault status:

1 – indicates that remote 3 diode has an "open" fault

0 – indicates that remote 3 diode does not have an "open" fault

4 R3DS RO Remote 3 diode short fault status:

1 – indicates that remote 3 diode has a "short" fault

0 – indicates that remote 3 diode does not have a "short" fault

3 R2DO RO Remote 2 diode open fault status:

1 – indicates that remote 2 diode has an "open" fault

0 – indicates that remote 2 diode does not have an "open" fault

2 R2DS RO Remote 2 diode short fault status:

1 – indicates that remote 2 diode has a "short" fault

0 – indicates that remote 2 diode does not have a "short" fault

1 R1DO RO Remote 1 diode open fault status:

1 – indicates that remote 1 diode has an "open" fault

0 – indicates that remote 1 diode does not have an "open" fault

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Bit(s) Bit Name Read/Write Description

0 R1DS RO Remote 1 diode short fault status:

1 – indicates that remote 1 diode has a "short" fault

0 – indicates that remote 1 diode does not have a "short" fault

7.5.1.4.3 Status 2 (TCRIT1)

Status bits for TCRIT1. When one or more of these bits are set and if not masked the TCRIT1 output will

activate. TCRIT1 will deactivate when all these bits are cleared.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 2 (TCRIT1) 0×08 RO – – – R4T1 R3T1 R2T1 R1T1 LT1 –

Bit(s) Bit Name Read/Write Description

7–5 - RO Reserved – will report 0 when read.

4 R4T1 RO Remote 4 Tcrit Status:

1 – indicates that remote 4 reading is greater than or equal to the value set in Remote 4 Tcrit

Limit register

0 – indicates that that remote 4 reading is less than the value set in Remote 4 Tcrit Limit register

minus the Common Hysteresis value

3 R3T1 RO Remote 3 Tcrit Status:

1 – indicates that remote 3 reading is greater than or equal to the value set in Remote 3 Tcrit

Limit register

0 – indicates that that remote 3 reading is less than the value set in Remote 3 Tcrit Limit register

minus the Common Hysteresis value

2 R2T1 RO Remote 2 Tcrit-1 Status:

1 – indicates that remote 2 reading is greater than or equal to the value set in Remote 2 Tcrit-1

Limit register

0 – indicates that that remote 2 reading is less than the value set in Remote 2 Tcrit-1 Limit

1 R1T1 RO Remote 1 Tcrit-1 Status:

1 – indicates that remote 1 reading is greater than or equal to the value set in Remote 1 Tcrit-1

Limit register

0 – indicates that that remote 1 reading is less than the value set in Remote 1 Tcrit-1 Limit

0 LT1 RO Local Tcrit Status:

1 – indicates that local reading is greater than or equal to the value set in Local Tcrit Limit

0 – indicates that local reading is less than the value set in Local Tcrit Limit register minus the

Common Hysteresis value

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7.5.1.4.4 Status 3 (TCRIT2)

Status bits for TCRIT2. When one or more of these bits are set and if not masked the TCRIT2 output will

activate. TCRIT2 will deactivate when all these bits are cleared.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 3 (TCRIT2) 0×09 RO – – – R4T2 R3T2 R2T2 R1T2 LT2 –

Bit(s) Bit Name Read/Write Description

7–5 - RO Reserved – will report 0 when read.

4 R4T2 RO Remote 4 Tcrit Status:

1 – indicates that remote 4 reading is greater than or equal to the value set in Remote 4 Tcrit

Limit register

0 – indicates that that remote 4 reading is less than the value set in Remote 4 Tcrit Limit register

minus the Common Hysteresis value

3 R3T2 RO Remote 3 Tcrit Status:

1 – indicates that remote 3 reading is greater than or equal to the value set in Remote 3 Tcrit

Limit register

0 – indicates that that remote 3 reading is less than the value set in Remote 3 Tcrit Limit register

minus the Common Hysteresis value

2 R2T2 RO Remote 2 Tcrit-2 Status:

1 – indicates that remote 2 reading is greater than or equal to the value set in Remote 2 Tcrit-2

Limit register

0 – indicates that that remote 2 reading is less than the value set in Remote 2 Tcrit-2 Limit

1 R1T2 RO Remote 1 Tcrit-2 Status:

1 – indicates that remote 1 reading is greater than or equal to the value set in Remote 1 Tcrit-2

Limit register

0 – indicates that that remote 1 reading is less than the value set in Remote 1 Tcrit-2 Limit

0 LT2 RO Local Tcrit Status:

1 – indicates that local reading is greater than or equal to the value set in Local Tcrit Limit

0 – indicates that local reading is less than the value set in Local Tcrit Limit register minus the

Common Hysteresis value

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7.5.1.4.5 Status 4 (TCRIT3)

Status bits for TCRIT3. When one or more of these bits are set and if not masked the TCRIT3 output will

activate. TCRIT3 will deactivate when all these bits are cleared.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 4 (TCRIT3) 0×0A RO – – – R4T3 R3T3 R2T3 R1T3 LT3 –

Bit(s) Bit Name Read/Write Description

7–5 - RO Reserved – will report 0 when read.

4 R4T3 RO Remote 4 Tcrit Status:

1 – indicates that remote 4 reading is greater than or equal to the value set in Remote 4 Tcrit

Limit register

0 – indicates that that remote 4 reading is less than the value set in Remote 4 Tcrit Limit register

minus the Common Hysteresis value

3 R3T3 RO Remote 3 Tcrit Status:

1 – indicates that remote 3 reading is greater than or equal to the value set in Remote 3 Tcrit

Limit register

0 – indicates that that remote 3 reading is less than the value set in Remote 3 Tcrit Limit register

minus the Common Hysteresis value

2 R2T3 RO Remote 2 Tcrit-2 Status:

1 – indicates that remote 2 reading is greater than or equal to the value set in Remote 2 Tcrit-2

Limit register

0 – indicates that that remote 2 reading is less than the value set in Remote 2 Tcrit-2 Limit

1 R1T3 RO Remote 1 Tcrit-2 Status:

1 – indicates that remote 1 reading is greater than or equal to the value set in Remote 1 Tcrit-2

Limit register

0 – indicates that that remote 1 reading is less than the value set in Remote 1 Tcrit-2 Limit

0 LT3 RO Local Tcrit Status:

1 – indicates that local reading is greater than or equal to the value set in Local Tcrit Limit

0 – indicates that local reading is less than the value set in Local Tcrit Limit register minus the

Common Hysteresis value

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7.5.1.5 Mask Registers

7.5.1.5.1 TCRIT1 Mask Register

The mask bits in this register allow control over which error events propagate to the TCRIT1 pin.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

TCRIT1 Mask 0×0C R/W – – – R4TM R3TM R2T1

MR1T1

MLTM 0×19

Bit(s) Bit Name Read/Write Description

7-5 – RO Reserved – will report 0 when read.

4 R4TM R/W Remote 4 Tcrit Mask:

1 – prevents the remote 4 temperature error event from propagating to the TCRIT1 pin

0 – allows the remote 4 temperature error event to propagate to the TCRIT1 pin

3 R3TM R/W Remote 3 Tcrit Mask:

1 – prevents the remote 3 temperature error event from propagating to the TCRIT1 pin

0 – allows the remote 3 temperature error event to propagate to the TCRIT1 pin

2 R2T1M R/W Remote 2 Tcrit-1 Mask:

1 – prevents the remote 2 temperature error event from propagating to the TCRIT1 pin

0 – allows the remote 2 temperature error event to propagate to the TCRIT1 pin

1 R1T1M R/W Remote 1 Tcrit-1 Mask:

1 – prevents the remote 1 temperature error event from propagating to the TCRIT1 pin

0 – allows the remote 1 temperature error event to propagate to the TCRIT1 pin

0 LTM R/W Local Tcrit Mask:

1 – prevents the local temperature error event from propagating to the TCRIT1 pin

0 – allows the local temperature error event to propagate to the TCRIT1 pin

7.5.1.5.2 TCRIT2 Mask Registers

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

TCRIT2 Mask 0×0D R/W – – – R4TM R3TM R2T2

MR1T2

MLTM 0×00

Bit(s) Bit Name Read/Write Description

7-5 – RO Reserved – will report 0 when read.

4 R4TM R/W Remote 4 Tcrit Mask:

1 – prevents the remote 4 temperature error event from propagating to the TCRIT2 pin

0 – allows the remote 4 temperature error event to propagate to the TCRIT2 pin

3 R3TM R/W Remote 3 Tcrit Mask:

1 – prevents the remote 3 temperature error event from propagating to the TCRIT2 pin

0 – allows the remote 3 temperature error event to propagate to the TCRIT2 pin

2 R2T2M R/W Remote 2 Tcrit-2 Mask:

1 – prevents the remote 2 temperature error event from propagating to the TCRIT2 pin

0 – allows the remote 2 temperature error event to propagate to the TCRIT2 pin

1 R1T2M R/W Remote 1 Tcrit-2 Mask:

1 – prevents the remote 1 temperature error event from propagating to the TCRIT2 pin

0 – allows the remote 1 temperature error event to propagate to the TCRIT2 pin

0 LTM R/W Local Tcrit Mask:

1 – prevents the local temperature error event from propagating to the TCRIT2 pin

0 – allows the local temperature error event to propagate to the TCRIT2 pin

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7.5.1.5.3 TCRIT3 Mask Register

The mask bits in this register allow control over which error events propagate to the TCRIT3 pin.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

TCRIT3 Mask 0×0E R/W – – – R4TM R3TM R2T2

MR1T2

MLTM 0×07

Bit(s) Bit Name Read/Write Description

7-5 – RO Reserved – will report 0 when read.

4 R4TM R/W Remote 4 Tcrit Mask:

1 – prevents the remote 4 temperature error event from propagating to the TCRIT3 pin

0 – allows the remote 4 temperature error event to propagate to the TCRIT3 pin

3 R3TM R/W Remote 3 Tcrit Mask:

1 – prevents the remote 3 temperature error event from propagating to the TCRIT3 pin

0 – allows the remote 3 temperature error event to propagate to the TCRIT3 pin

2 R2T2M R/W Remote 2 Tcrit-2 Mask:

1 – prevents the remote 2 temperature error event from propagating to the TCRIT3 pin

0 – allows the remote 2 temperature error event to propagate to the TCRIT3 pin

1 R1T2M R/W Remote 1 Tcrit-2 Mask:

1 – prevents the remote 1 temperature error event from propagating to the TCRIT3 pin

0 – allows the remote 1 temperature error event to propagate to the TCRIT3 pin

0 LTM R/W Local Tcrit Mask:

1 – prevents the local temperature error event from propagating to the TCRIT3 pin

0 – allows the local temperature error event to propagate to the TCRIT3 pin

7.5.1.6 Limit Registers

7.5.1.6.1 Local Limit Register

The Local Limit register range is 0°C to 127°C. The value programmed in this register is used to determine a

local temperature error event.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Local Tcrit Limit 0×40 R/W 0 64 32 16 8 4 2 1 0×55

Bit(s) Bit Name Read/Write Description

7 0 R0 Read only bit will always report 0.

6 64 R/W bit weight 64°C

5 32 R/W bit weight 32°C

4 16 R/W bit weight 16°C

3 8 R/W bit weight 8°C

2 4 R/W bit weight 4°C

1 2 R/W bit weight 2°C

0 1 R/W bit weight 1°C

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7.5.1.6.2 Remote Limit Registers

The range for these registers is 0°C to 255°C.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote 1 Tcrit-1 Limit (used by

TCRIT1 error events) 0x41 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 2 Tcrit-1 Limit (used by

TCRIT1 error events) 0x42 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 3 Tcrit Limit (used by TCRIT1,

TCRIT2 and TCRIT3 error events) 0x43 R/W 128 64 32 16 8 4 2 1 0x55

Remote 4 Tcrit Limit (used by TCRIT1,

TCRIT2 and TCRIT3 error events) 0x44 R/W 128 64 32 16 8 4 2 1 0x55

Remote 1 Tcrit-2 and Tcrit3 Limit (used

by TCRIT2 and TCRIT3 error events) 0x49 R/W 128 64 32 16 8 4 2 1 0x55

Remote 2 Tcrit-2 and Tcrit3 Limit (used

by TCRIT2 and TCRIT3 error events) 0x4A R/W 128 64 32 16 8 4 2 1 0x55

Bit(s) Bit Name Read/Write Description

7 128 R/W bit weight 128°C

6 64 R/W bit weight 64°C

5 32 R/W bit weight 32°C

4 16 R/W bit weight 16°C

3 8 R/W bit weight 8°C

2 4 R/W bit weight 4°C

1 2 R/W bit weight 2°C

0 1 R/W bit weight 1°C

Limit assignments for each TCRIT output pin:

OUTPUT PIN REMOTE 4 REMOTE 3 REMOTE 2 REMOTE 1 LOCAL

TCRIT1 Remote 4 Tcrit Limit Remote 3 Tcrit Limit Remote 2 Tcrit-1

Limit Remote 1 Tcrit-1

Limit Local Tcrit Limit

TCRIT2 Remote 4 Tcrit Limit Remote 3 Tcrit Limit Remote 2 Tcrit-2

Limit Remote 1 Tcrit-2

Limit Local Tcrit Limit

TCRIT3 Remote 4 Tcrit Limit Remote 3 Tcrit Limit Remote 2 Tcrit-2

Limit Remote 1 Tcrit-2

Limit Local Tcrit Limit

LM95214

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7.5.1.6.3 Common Tcrit Hysteresis Register

The hysteresis register range is 0°C to 32°C. The value programmed in this register is used to modify all the limit

values for decreasing temperature.

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Common Tcrit Hysteresis 0×5A R/W 0 0 0 16 8 4 2 1 0×0A

Bit(s) Bit Name Read/Write Description

7 0 RO Read only bit will always report 0.

6 0 RO Read only bit will always report 0.

5 0 RO Read only bit will always report 0.

4 16 R/W bit weight 16°C

3 8 R/W bit weight 8°C

2 4 R/W bit weight 4°C

1 2 R/W bit weight 2°C

0 1 R/W bit weight 1°C

7.5.1.7 Identification Registers

Byte

(Hex)

Read/

Write D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Manufacturer ID 0×FE RO 0 0 0 0 0 0 0 1 0×01

Revision ID 0×FF RO 0 1 1 1 1 0 0 1 0×79

SMBus

Master

* Note, place close to LM95214 pins.

** Note, optional - place close to LM95214 pins.

LM95214

VDD

D4+

D3+

SMBCLK

C1*

100 pF

0.1 PF

SMBCLK

SMBDAT

C7**

100 pF

+3.3V

Standby

1.3k R5

1.3k

D-

D2+

D1+

SMBDAT

MMBT3904

C6**

100 pF

C4**

100 pF

C5**

100 pF

10k

Ambient

Board

Processor

10 PF

TCRIT2

TCRIT1

TCRIT3

GND

ASIC

LM95214

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Product Folder Links: LM95214

8 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component

specification, and TI does not warrant its accuracy or completeness. TI’s customers are

responsible for determining suitability of components for their purposes. Customers should

validate and test their design implementation to confirm system functionality.

8.1 Application Information

The LM95214 can be applied easily in the same way as other integrated-circuit temperature sensors, and its

remote diode sensing capability allows it to be used in new ways as well. It can be soldered to a printed-circuit

board, and because the path of best thermal conductivity is between the die and the pins, its temperature will

effectively be that of the printed-circuit board lands and traces soldered to the LM95214's pins. This presumes

that the ambient air temperature is almost the same as the surface temperature of the printed-circuit board; if the

air temperature is much higher or lower than the surface temperature, the actual temperature of the LM95214 die

will be at an intermediate temperature between the surface and air temperatures. Again, the primary thermal

conduction path is through the leads, so the circuit board temperature will contribute to the die temperature much

more strongly than will the air temperature.

8.2 Typical Application

To measure temperature external to the LM95214's die, incorporates remote diode sensing technology. This

diode can be located on the die of a target IC, allowing measurement of the IC's temperature, independent of the

LM95214's temperature. A discrete diode can also be used to sense the temperature of external objects or

ambient air. Remember that a discrete diode's temperature will be affected, and often dominated, by the

temperature of its leads. Most silicon diodes do not lend themselves well to this application. TI recommends that

an MMBT3904 transistor base emitter junction be used with the collector tied to the base.

The LM95214 can measure a diode-connected transistor such as the MMBT3904 or the thermal diode found in

an AMD processor. The LM95214 has been optimized to measure the MMBT3904 remote thermal diode the

offset register can be used to calibrate for other thermal diodes easily. The LM95214 does not include

TruTherm™ technology that allows sensing of sub-micron geometry process thermal diodes. For this application

the LM95234 would be better suited.

The LM95234 has been specifically optimized to measure the remote thermal diode integrated in a typical Intel

processor on 65 nm or 90 nm process or an MMBT3904 transistor. Using the Remote Diode Model Select

nm or 90 nm process or an MMBT3904.

Figure 25. Typical Application

T = q x 'VBE

x k x ln IF2

IF1

x='ln

BE I

I=Ix

§¹

Sxe

I=Ix

§¹

Sxe

-1

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Product Folder Links: LM95214

Typical Application (continued)

8.2.1 Design Requirements

The LM95214 operates only as a slave device and communicates with the host through the SMBus serial

interface essentially compatible with I2C. SMBCLK is the clock input pin, SMBDATA is a bidirectional data pin,

and TCRIT1, TCRIT2, TCRIT3 are the output pins. The LM95214 requires a pullup resistor on the SMBCLK,

SMBDATA, and TCRIT1, TCRIT2, TCRIT3 pins due to an open-drain output. It is very important to consider the

pullup resistor for the I2C systems. The recommended value for the pullup resistors is in Figure 25. Use a

ceramic capacitor type with a temperature rating from –40°C to +125°C, placed as close as possible to the VDD

pin of the LM95214. The decoupling capacitor reduces any noise induced by the system. A0 (pin 6) can be

connected to either Low, Mid-Supply or High voltages for address selection for configuring three possible unique

slave ID addresses; SMBus Interface explains the addressing scheme.

8.3 Diode Non-Ideality

8.3.1 Diode Non-Ideality Factor Effect on Accuracy

When a transistor is connected as a diode, the following relationship holds for variables VBE, T and IF:

where

•

• q = 1.6 × 10−19 Coulombs (the electron charge)

• T = Absolute Temperature in Kelvin

• k = 1.38 × 10−23 joules/K (Boltzmann's constant)

•ηis the non-ideality factor of the process the diode is manufactured on

• IS= Saturation Current and is process dependent

• If= Forward Current through the base-emitter junction

• VBE = Base-Emitter Voltage drop (1)

In the active region, the –1 term is negligible and may be eliminated, yielding Equation 2

(2)

In Equation 2,ηand ISare dependant upon the process that was used in the fabrication of the particular diode.

By forcing two currents with a very controlled ratio(IF2 / IF1) and measuring the resulting voltage difference, it is

possible to eliminate the ISterm. Solving for the forward voltage difference yields the relationship:

(3)

Solving Equation 3 for temperature yields:

(4)

Equation 4 holds true when a diode connected transistor such as the MMBT3904 is used. When this diode

equation is applied to an integrated diode such as a processor transistor with its collector tied to GND as shown

in Figure 26 it will yield a wide non-ideality spread. This wide non-ideality spread is not due to true process

variation but due to the fact that Equation 4 is an approximation.

xPCB

62.0

MMBT3904

LM95214

100 pF

ASIC

ICIR

IE = IF

100 pF

D1+

D2+

5D-

Tqx'BE

xln ¸

§I2C

I1C

LM95214

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Product Folder Links: LM95214

Diode Non-Ideality (continued)

Texas Instruments invented TruTherm beta cancellation technology that uses the transistor equation, Equation 5,

which is a more accurate representation of the topology of the thermal diode found in some sub-micron FPGAs

or processors.

(5)

Figure 26. Thermal Diode Current Paths

TruTherm technology can be found in the LM95234 four channel remote diode sensor that is pin and register

compatible with the LM95214. The LM95214 does not support this technology.

8.3.2 Calculating Total System Accuracy

The voltage seen by the LM95214 also includes the IFRSvoltage drop of the series resistance. The non-ideality

factor, η, is the only other parameter not accounted for and depends on the diode that is used for measurement.

Because ΔVBE is proportional to both ηand T, the variations in ηcannot be distinguished from variations in

temperature. Because the non-ideality factor is not controlled by the temperature sensor, it will directly add to the

inaccuracy of the sensor. For the for Intel processor on 65 nm process, Intel specifies a +4.06%/−0.897%

variation in ηfrom part to part when the processor diode is measured by a circuit that assumes diode equation,

Equation 4, as true. As an example, assume a temperature sensor has an accuracy specification of ±1.0°C at a

temperature of 80°C (353 Kelvin) and the processor diode has a non-ideality variation of +1.19%/−0.27%. The

resulting system accuracy of the processor temperature being sensed will be:

TACC = + 1.0°C + (+4.06% of 353 K) = +15.3°C

and TACC = –1.0°C + (−0.89% of 353 K) = –4.1°C

The next error term to be discussed is that due to the series resistance of the thermal diode and printed-circuit

board traces. The thermal diode series resistance is specified on most processor data sheets. For the

MMBT3904 transistor, this is specified at 0 Ωtypical. The LM95214 accommodates the typical series resistance

of a circuit with the offset register compensation. The error that is not accounted for is the spread of the thermal

diodes series resistance. If a circuit has a series resistance spread that is 2.79 Ωto 6.24 Ωor 4.515 Ω±1.73 Ω,

the 4.515 Ωcan be cancelled out with the offset register setting. The ±1.73 Ωspread cannot be cancelled out.

The equation to calculate the temperature error due to series resistance (TER) for the LM95214 is simply:

(6)

Solving Equation 6 for RPCB equal to ±1.73 Ωresults in the additional error due to the spread in the series

resistance of ±1.07°C. The bulk of the error caused by the 4.515 Ωwill cause a positive offset in the temperature

reading of 2.79°C, which can be cancelled out by setting the offset register to –2.75°C. The spread in error

cannot be canceled out, as it would require measuring each individual thermal diode device. This is quite difficult

and impractical in a large volume production environment.

TCF = (80 + 273) = -1.75oC

1.003 - 1.008

1.003 ¹

TCF = (TCR + 273K)

KS - KPROCESSOR

KS¹

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Diode Non-Ideality (continued)

Equation 6 can also be used to calculate the additional error caused by series resistance on the printed circuit

board. Because the variation of the PCB series resistance is minimal, the bulk of the error term is always positive

and can simply be cancelled out by subtracting it from the output readings of the LM95214.

PROCESSOR FAMILY DIODE EQUATION ηD, non-ideality SERIES R,Ω

MIN TYP MAX

Pentium III CPUID 67h 1 1.0065 1.0125

Pentium III CPUID 68h/PGA370Socket/

Celeron 1.0057 1.008 1.0125

Pentium 4, 423 pin 0.9933 1.0045 1.0368

Pentium 4, 478 pin 0.9933 1.0045 1.0368

Pentium 4 on 0.13 micron process, 2 - 3.06

GHz 1.0011 1.0021 1.0030 3.64

Pentium 4 on 90 nm process 1.0083 1.011 1.023 3.33

Intel Processor on 65 nm process 1.000 1.009 1.050 4.52

Pentium M (Centrino) 1.00151 1.00220 1.00289 3.06

MMBT3904 1.003

AMD Athlon MP model 6 1.002 1.008 1.016

AMD Athlon 64 1.008 1.008 1.096

AMD Opteron 1.008 1.008 1.096

AMD Sempron 1.00261 0.93

8.3.3 Compensating for Different Non-Ideality

To compensate for the errors introduced by non-ideality, the temperature sensor is calibrated for a particular

processor. Texas Instruments temperature sensors are always calibrated to the typical non-ideality and series

resistance of a given transistor type. The LM95214 is calibrated for the non-ideality factor and series resistance

values of the MMBT3904 transistor without the requirement for additional trims. When a temperature sensor

calibrated for a particular thermal diode type is used with a different thermal diode type, additional errors are

introduced.

Temperature errors associated with non-ideality of different processor types may be reduced in a specific

temperature range of concern through use of software calibration. Typical Non-ideality specification differences

cause a gain variation of the transfer function, therefore the center of the temperature range of interest must be

the target temperature for calibration purposes. The Equation 7 can be used to calculate the temperature

correction factor (TCF) required to compensate for a target non-ideality differing from that supported by the

LM95214.

where

•ηS= LM95214 non-ideality for accuracy specification

•ηPROCESSOR = Processor thermal diode typical non-ideality

• TCR = center of the temperature range of interest in °C (7)

The correction factor must be directly added to the temperature reading produced by the LM95214. For example

when using the LM95214, with the 3904 mode selected, to measure a AMD Athlon processor, with a typical non-

ideality of 1.008, for a temperature range of 60°C to 100°C the correction factor would calculate to:

(8)

Therefore, 1.75°C must be subtracted from the temperature readings of the LM95214 to compensate for the

differing typical non-ideality target.

LM95214

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Product Folder Links: LM95214

9 Power Supply Recommendations

The LM95214 operates on a power-supply range from 3.0 V to 3.6 V. A power-supply bypass capacitor is

required, which much be placed as close as possible to the supply and ground pins of the device. A typical value

for this supply bypass capacitor is 100 nF. Applications with noisy or high-impedance power supplies may require

additional decoupling capacitors to reject power-supply noise.

LM95214

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Product Folder Links: LM95214

10 Layout

10.1 Layout Guidelines

In a noisy environment, such as a processor mother board, layout considerations are very critical. Noise induced

on traces running between the remote temperature diode sensor and the LM95214 can cause temperature

conversion errors. Keep in mind that the signal level the LM95214 is trying to measure is in microvolts. The

following guidelines must be followed:

1. VDD must be bypassed with a 0.1-µF capacitor in parallel with 100 pF. The 100-pF capacitor must be placed

as close as possible to the power supply pin. A bulk capacitance of approximately 10 µF must be in the near

vicinity of the LM95214.

2. Ti recommends the use of a 100-pF diode bypass capacitor to filter high-frequency noise, but it may not be

necessary. Make sure the traces to the 100-pF capacitor are matched. Place the filter capacitors close to the

LM95214 pins.

3. Ideally, the LM95214 must be placed within 10 cm of the Processor diode pins with the traces being as

straight, short and identical as possible. Trace resistance of 1 Ωcan cause as much as 0.62°C of error. This

error can be compensated by using simple software offset compensation.

4. Diode traces must be surrounded by a GND guard ring to either side, above and below if possible. This GND

guard must not be between the D+ and D−lines. In the event that noise does couple to the diode lines it

would be ideal if it is coupled common mode. That is equally to the D+ and D−lines.

5. Avoid routing diode traces in close proximity to power supply switching or filtering inductors.

6. Avoid running diode traces close to or parallel to high-speed digital and bus lines. Diode traces must be kept

at least 2 cm apart from the high-speed digital traces.

7. If it is necessary to cross high-speed digital traces, the diode traces and the high-speed digital traces must

cross at a 90 degree angle.

8. The ideal place to connect the LM95214's GND pin is as close as possible to the Processors GND

associated with the sense diode.

9. Leakage current between D+ and GND and between D+ and D−must be kept to a minimum. Thirteen nano-

amperes of leakage can cause as much as 0.2°C of error in the diode temperature reading. Keeping the

printed-circuit board as clean as possible will minimize leakage current.

Noise coupling into the digital lines greater than 400 mVp-p (typical hysteresis) and undershoot less than 500 mV

below GND, may prevent successful SMBus communication with the LM95214. SMBus no acknowledge is the

most common symptom, causing unnecessary traffic on the bus. Although the SMBus maximum frequency of

communication is rather low (100 kHz maximum), care still needs to be taken to ensure proper termination within

a system with multiple parts on the bus and long printed-circuit board traces. An RC lowpass filter with a 3-dB

corner frequency of about 40 MHz is included on the LM95214's SMBCLK input. Additional resistance can be

added in series with the SMBDAT and SMBCLK lines to further help filter noise and ringing. Minimize noise

coupling by keeping digital traces out of switching power supply areas as well as ensuring that digital lines

containing high-speed data communications cross at right angles to the SMBDAT and SMBCLK lines.

10.2 Layout Example

Figure 27. Ideal Diode Trace Layout

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11 Device and Documentation Support

11.1 Receiving Notification of Documentation Updates

To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper

right corner, click on Alert me to register and receive a weekly digest of any product information that has

changed. For change details, review the revision history included in any revised document.

11.2 Community Resources

The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective

contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of

Use.

TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration

among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help

solve problems with fellow engineers.

Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and

contact information for technical support.

11.3 Trademarks

E2E is a trademark of Texas Instruments.

All other trademarks are the property of their respective owners.

11.4 Electrostatic Discharge Caution

This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with

appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.

ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more

susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.

11.5 Glossary

SLYZ022 —TI Glossary.

This glossary lists and explains terms, acronyms, and definitions.

12 Mechanical, Packaging, and Orderable Information

The following pages include mechanical, packaging, and orderable information. This information is the most

current data available for the designated devices. This data is subject to change without notice and revision of

this document. For browser-based versions of this data sheet, refer to the left-hand navigation.

PACKAGE OPTION ADDENDUM

www.ti.com 10-Dec-2020

Addendum-Page 1

PACKAGING INFORMATION

Orderable Device Status

(1)

Package Type Package

Drawing Pins Package

Qty Eco Plan

(2)

Lead finish/

Ball material

(6)

MSL Peak Temp

(3)

Op Temp (°C) Device Marking

(4/5)

Samples

LM95214CISD/NOPB ACTIVE WSON NHL 14 1000 RoHS & Green SN Level-1-260C-UNLIM -40 to 140 95214CI

LM95214CISDX/NOPB ACTIVE WSON NHL 14 4500 RoHS & Green SN Level-1-260C-UNLIM -40 to 140 95214CI

(1) The marketing status values are defined as follows:

ACTIVE: Product device recommended for new designs.

LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.

NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.

PREVIEW: Device has been announced but is not in production. Samples may or may not be available.

OBSOLETE: TI has discontinued the production of the device.

(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance

do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may

reference these types of products as "Pb-Free".

RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.

Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based

flame retardants must also meet the <=1000ppm threshold requirement.

(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.

(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.

(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation

of the previous line and the two combined represent the entire Device Marking for that device.

(6) Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two

lines if the finish value exceeds the maximum column width.

Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information

provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and

continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.

TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.

In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.

PACKAGE OPTION ADDENDUM

www.ti.com 10-Dec-2020

Addendum-Page 2

TAPE AND REEL INFORMATION

*All dimensions are nominal

Device Package

Type Package

Drawing Pins SPQ Reel

Diameter

(mm)

Reel

Width

W1 (mm)

(mm) B0

(mm) K0

(mm) P1

(mm) W

(mm) Pin1

Quadrant

LM95214CISD/NOPB WSON NHL 14 1000 178.0 12.4 4.3 4.3 1.3 8.0 12.0 Q1

LM95214CISDX/NOPB WSON NHL 14 4500 330.0 12.4 4.3 4.3 1.3 8.0 12.0 Q1

PACKAGE MATERIALS INFORMATION

www.ti.com 8-Aug-2017

Pack Materials-Page 1

*All dimensions are nominal

Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)

LM95214CISD/NOPB WSON NHL 14 1000 210.0 185.0 35.0

LM95214CISDX/NOPB WSON NHL 14 4500 367.0 367.0 35.0

PACKAGE MATERIALS INFORMATION

www.ti.com 8-Aug-2017

Pack Materials-Page 2

MECHANICAL DATA

NHL0014B

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SDA14B (Rev A)

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