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LP2952-N

LP2952A

LP2953

LP2953A

SNVS095F –MAY 2004–REVISED MARCH 2015

LP295x Adjustable Micropower Low-Dropout Voltage Regulators

1 Features 3 Description

The LP2952 and LP2953 are micropower voltage

1• 2.3-V to 30-V Input Voltage Range regulators with very low quiescent current (130 μA

• Output Voltage Adjusts from 1.23 V to 29 V typical at 1-mA load) and very low dropout voltage

• 250-mA Output Current (typically 60 mV at light load and 470 mV at 250-mA

load current). They are ideally suited for battery-

• Extremely Low Quiescent Current powered systems. Furthermore, the quiescent current

• Low Dropout Voltage increases only slightly at dropout, which prolongs

• Extremely Tight Line and Load Regulation battery life.

• Very Low Temperature Coefficient The LP2952 and LP2953 retain all the desirable

• Current and Thermal Limiting characteristics of the LP2951, but offer increased

output current, additional features, and an improved

• Reverse Battery-Input Protection shutdown function.

• 50-mA (Typical) Automatic Output Discharge The automatic output discharge pulls the output down

• LP2953 Versions Only quickly when the shutdown is activated.

– Auxiliary Comparator Included With CMOS-

and TTL-Compatible Output Levels. Can Be The error flag goes low if the output voltage drops out

of regulation.

Used for Fault Detection, Low-Input Line

Detection, and so on. Reverse battery-input protection is provided.

The internal voltage reference is made available for

2 Applications external use, providing a low temperature coefficient

• High-Efficiency Linear Regulator (20 ppm/°C) reference with very good line (0.03%)

and load (0.04%) regulation.

• Regulator With Undervoltage Shutdown

• Low-Dropout Battery-Powered Regulator Device Information(1)

• Snap-ON/Snap-OFF Regulator PART NUMBER PACKAGE BODY SIZE (NOM)

LP2952x SOIC (16) 9.90 mm × 3.91 mm

SOIC (16) 9.90 mm × 3.91 mm

LP2953x PDIP (16) 21.755 mm × 6.35 mm

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

the end of the data sheet.

Typical Application Schematic

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.

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Table of Contents

7.3 Feature Description................................................. 15

1 Features.................................................................. 17.4 Device Functional Mode ......................................... 16

2 Applications ........................................................... 18 Application and Implementation ........................ 17

3 Description............................................................. 18.1 Application Information............................................ 17

4 Revision History..................................................... 28.2 Typical Applications ................................................ 21

5 Pin Configuration and Functions......................... 39 Power Supply Recommendations...................... 30

6 Specifications......................................................... 410 Layout................................................................... 31

6.1 Absolute Maximum Ratings ...................................... 410.1 Layout Guidelines ................................................. 31

6.2 ESD Ratings.............................................................. 410.2 Layout Example .................................................... 31

6.3 Recommended Operating Conditions....................... 410.3 Power Dissipation: Heatsink Requirements

6.4 Thermal Information.................................................. 5(Industrial Temperature Range Devices)................. 32

6.5 Electrical Characteristics: 3.3-V Versions................. 511 Device and Documentation Support................. 34

6.6 Electrical Characteristics: 5-V Versions.................... 511.1 Related Links ........................................................ 34

6.7 Electrical Characteristics: All Voltage Options.......... 611.2 Trademarks........................................................... 34

6.8 Typical Characteristics.............................................. 911.3 Electrostatic Discharge Caution............................ 34

7 Detailed Description............................................ 14 11.4 Glossary................................................................ 34

7.1 Overview................................................................. 14 12 Mechanical, Packaging, and Orderable

7.2 Functional Block Diagrams ..................................... 14 Information ........................................................... 34

4 Revision History

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

Changes from Revision E (December 2014) to Revision F Page

• Deleted "Assured" .................................................................................................................................................................. 1

• Changed "Output Pulldown Crowbar" to "Automatic Output Discharge" ............................................................................... 1

• Changed "internal crowbar" to "automatic output discharge"................................................................................................. 1

• Added word "input" after "battery" in Features and Description............................................................................................. 1

• Changed pin names for IN and OUT to match TI nomenclature; fix typos............................................................................ 1

• Changed max junc. temp from 125°C to 150°C .................................................................................................................... 4

• Changed wording of footnote 12 ........................................................................................................................................... 8

• Added second bullet for "LP2953 versions only" ................................................................................................................. 14

• Added Automatic Output Dischange subsection ................................................................................................................. 16

• Deleted sentence "To achieve the smallest form factor, the TO-92 package is selected.".................................................. 22

• Changed "With an efficiency of 83.3% and a 250-mA maximum load, the internal power dissipation is 250 mW,

which corresponds to a 19.2°C junction temperature rise for the SOIC package." to "With a VIN – VOUT differential of

1 V and a maximum load current of 250 mA the internal junction temperature (TJ) of the SOIC package will rise

19.2° above the ambient temperature."................................................................................................................................ 22

• Deleted "Thermal Resistance for Various Copper Heatsinking Patterns" table................................................................... 33

Changes from Revision D (September 2013) to Revision E Page

• Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional

Modes,Application and Implementation section, Power Supply Recommendations section, Layout section, Device

and Documentation Support section, and Mechanical, Packaging, and Orderable Information section; updated

Thermal Information values; deleted obsolete LP2953AM references .................................................................................. 1

Changes from Revision C (March 2005) to Revision D Page

• Changed layout of National Data Sheet to TI format ........................................................................................................... 30

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5 Pin Configuration and Functions

16 Pins 16 Pins

LP2952 SOIC (D) Package LP2953 SOIC (D) Package

Top View Top View

16 Pins

LP2953 PDIP (NBG) Package

Top View

Pin Functions LP2952-N

PIN I/O DESCRIPTION

NAME SOIC(D)

ERROR 6 O Error signal output

FEEDBACK 14 I Error amplifier noninverting input

GROUND 1, 8, 9, 16 - Ground

IN 15 I Regulator power input

NC 2, 7, 10, 11 - NC

OUT 3 O Regulated output voltage

REFERENCE 12 O Internal reference voltage output

SENSE 4 I Feedback voltage sense input

SHUTDOWN 5 I Shutdown input

VTAP 13 I Internal resistor divider input

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Pin Functions LP2953

PIN I/O DESCRIPTION

NAME SOIC(D) PDIP(NBG)

COMPIN 10 15 I Auxiliary comparator input

COMPOUT 11 14 O Auxiliary comparator output

ERROR 6 10 O Error signal output

FEEDBACK 14 2 I Error amplifier noninverting input

GROUND 1, 8, 9, 16 4, 5, 12, 13 - Ground

IN 15 3 I Regulator power input

NC 2, 7 7, 11 - NC

OUT 3 6 O Regulated output voltage

REFERENCE 12 16 O Internal reference voltage output

SENSE 4 8 I Feedback voltage sense input

SHUTDOWN 5 9 I Shutdown input

VTAP 13 1 I Internal resistor divider input

6 Specifications

6.1 Absolute Maximum Ratings

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

MIN MAX UNIT

Power dissipation(2) Internally Limited

Input supply voltage −20 30 V

FEEDBACK input voltage(3) −0.3 5 V

Comparator input voltage(4) −0.3 30 V

SHUTDOWN input voltage(4) −0.3 30 V

Comparator output voltage(4) −0.3 30 V

Maximum junction temperature 150 °C

Storage temperature, Tstg −65 150 °C

(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) The maximum allowable power dissipation is a function of the maximum junction temperature, TJ(MAX), the junction-to-ambient thermal

resistance, RθJA, and the ambient temperature, TA. The maximum allowable power dissipation at any ambient temperature is calculated

using the equation for P(MAX): P(MAX) = (TJ(MAX) – TA) / RθJA.

Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal

shutdown. See Power Supply Recommendations for additional information on heatsinking and thermal resistance.

(3) When used in dual-supply systems where the regulator load is returned to a negative supply, the output voltage must be diode-clamped

to ground.

(4) May exceed the input supply voltage.

6.2 ESD Ratings VALUE UNIT

Electrostatic Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins(1) ±2000

V(ESD) V

discharge

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

6.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted) MIN MAX UNIT

Operating junction temperature −40 125 °C

Input supply voltage 2.3 30 V

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6.4 Thermal Information LP2952, LP2953 LP2953

THERMAL METRIC(1) SOIC (D) PDIP (NBG) UNIT

16 PINS

RθJA Junction-to-ambient thermal resistance 76.9 42.1

RθJC(top) Junction-to-case (top) thermal resistance 37.4 28.1

RθJB Junction-to-board thermal resistance 34.6 22.2 °C/W

ψJT Junction-to-top characterization parameter 7.3 12.0

ψJB Junction-to-board characterization parameter 34.3 22.1

(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics: 3.3-V Versions

Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.

Unless otherwise specified: MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature

Range and TYP (typical) values apply at TJ= 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7

μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.

LP2952AI-3.3, LP2953AI-3.3 LP2952I-3.3, LP2953I-3.3

PARAMETER TEST CONDITIONS UNIT

MIN TYP MAX MIN TYP MAX

TJ= 25°C 3.284 3.3 3.317 3.267 3.3 3.333

VOUT Output voltage 3.260 3.3 3.340 3.234 3.3 3.366 V

1 mA ≤IOUT ≤250 mA 3.254 3.3 3.346 3.221 3.3 3.379

6.6 Electrical Characteristics: 5-V Versions

Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.

Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature

Range and TYP (typical) values apply at TJ= 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7

μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.

LP2952AI, LP2953AI LP2952I, LP2953I

PARAMETER TEST CONDITIONS UNIT

MIN TYP MAX MIN TYP MAX

TJ= 25°C 4.975 5 5.025 4.95 5 5.05

VOUT Output voltage 4.94 5 5.06 4.9 5 5.1 V

1 mA ≤IOUT ≤250 mA 4.93 5 5.07 4.88 5 5.12

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ûVOUT

ûPD

ûVOUT

ûV

ûVOUT

ûV

ûVOUT

ûT

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6.7 Electrical Characteristics: All Voltage Options

Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.

Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature

Range and TYP (typical) values apply at TJ= 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7

μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.

LP2952AI, LP2953AI, LP2952I, LP2953I,

LP2952AI-3.3, LP2953AI-3.3(1) LP2952I-3.3, LP2953I-3.3

PARAMETER TEST CONDITIONS UNIT

MIN TYP MAX MIN TYP MAX

REGULATOR

Output voltage

temperature See(2) 20 100 20 150 ppm/°C

coefficient TJ= 25°C 0.03% 0.1% 0.03% 0.2%

Output voltage VIN = VOUT(NOM) + 1 V to 30 V

line regulation VIN = VOUT(NOM) + 1 V to 30 V 0.03% 0.2% 0.03% 0.4%

TJ= 25°C 0.04% 0.16% 0.04% 0.20%

Output voltage IOUT = 1 mA to 250 mA

load regulation(3) IOUT = 0.1 mA to 1 mA 0.04% 0.20% 0.04% 0.30%

TJ= 25°C, IOUT = 1 mA 60 100 60 100

IOUT = 1 mA 60 150 60 150

IOUT = 50 mA 240 300 240 300

IOUT = 50 mA 240 420 240 420

Dropout

VIN – VOUT mV

voltage(4) TJ= 25°C, IOUT = 100 mA 310 400 310 400

IOUT = 100 mA 310 520 310 520

TJ= 25°C, IOUT = 250 mA 470 600 470 600

IOUT = 250 mA 470 800 470 800

TJ= 25°C, IOUT = 1 mA 130 170 130 170 μA

IOUT = 1 mA 130 200 130 200

TJ= 25°C, IOUT = 50 mA 1.1 2 1.1 2

IOUT = 50 mA 1.1 2.5 1.1 2.5

Ground pin

IGND current(5) TJ= 25°C, IOUT = 100 mA 4.5 6 4.5 6 mA

IOUT = 100 mA 4.5 8 4.5 8

TJ= 25°C, IOUT = 250 mA 21 28 21 28

IOUT = 250 mA 21 33 21 33

VIN = VOUT(NOM) −0.5 V 165 210 165 210

Ground pin

IGND current at μA

IOUT = 100 μA165 240 165 240

dropout –40°C ≤TJ≤125°C

Ground pin

IGND current at TJ= 25°C, VSHUTDOWN ≤1.1 V 105 140 105 140 μA

shutdown(5)

TJ= 25°C, VOUT = 0 380 500 380 500

ILIMIT Current limit mA

VOUT = 0 380 530 380 530

Thermal TJ= 25°C; see(6) 0.05 0.2 0.05 0.2 %/W

regulation

(1) Drive SHUTDOWN pin with TTL or CMOS low level to shut off regulator, high level to turn on regulator.

(2) Output or reference voltage temperature coefficient is defined as the worst-case voltage change divided by the total temperature range.

(3) Load regulation is measured at constant junction temperature using low duty-cycle pulse testing. Two separate tests are performed, one

for the range of IOUT = 100 μA to 1 mA and one for the range of IOUT =1 mA to 250 mA. Changes in output voltage due to heating

effects are covered by the thermal regulation specification.

(4) Dropout voltage is defined as the input-to-output differential at which the output voltage drops 100 mV below the value measured with a

1-V differential. At very low values of programmed output voltage, the input voltage minimum of 2 V (2.3 V over temperature) must be

observed.

(5) Ground pin current is the regulator quiescent current. The total current drawn from the source is the sum of the ground pin current,

output load current, and current through the external resistive divider (if used).

(6) Thermal regulation is the change in output voltage at a time t after a change in power dissipation, excluding load or line regulation

effects. Specifications are for a 200-mA load pulse at VIN = VOUT(NOM) + 15 V (3-W pulse) for t = 10 ms.

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Electrical Characteristics: All Voltage Options (continued)

Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.

Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature

Range and TYP (typical) values apply at TJ= 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7

μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.

LP2952AI, LP2953AI, LP2952I, LP2953I,

LP2952AI-3.3, LP2953AI-3.3(1) LP2952I-3.3, LP2953I-3.3

PARAMETER TEST CONDITIONS UNIT

MIN TYP MAX MIN TYP MAX

Output noise COUT = 4.7 μF 400 400

voltage (10 Hz μV

COUT = 33 μF 260 260

ento 100 kHz) RMS

COUT = 33 μF(7) 80 80

IOUT = 100 mA TJ= 25°C, see(8) 1.215 1.23 1.245 1.205 1.23 1.255

Reference

VREF V

voltage see(8), 1.205 1.255 1.19 1.27

Reference VIN = 2.5 V to VOUT + 1 V 0.03% 0.1% 0.03% 0.2%

voltage line VIN = VOUT(NOM)+ 1 V to 30 V(9) 0.03% 0.2% 0.03% 0.4%

regulation

Reference TJ= 25°C, IREF = 0 to 200 μA 0.25% 0.4% 0.25% 0.8%

voltage load IREF = 0 to 200 μA 0.25% 0.6% 0.25% 1.0%

regulation

Reference

voltage See(2), –40°C ≤TJ≤125°C 20 20 ppm/°C

temperature

coefficient TJ= 25°C 20 40 20 40

Feedback pin

IB(FB) nA

bias current 20 60 20 60

TJ= 25°C; see (10) 30 30

Output off

IO(SINK) mA

pulldown current See (10) 20 20

DROPOUT DETECTION COMPARATOR

TJ= 25°C, VOH = 30 V 0.01 1 0.01 1

Output high

IOH μA

leakage VOH = 30 V 0.01 2 0.01 2

TJ= 25°C, VIN = VOUT(NOM) −

0.5 V 150 250 150 250

Output low IOUT(COMP) = 400 μA

VOL mV

voltage VIN = VOUT(NOM) −0.5 V 150 400 150 400

IOUT(COMP) = 400 μA

TJ= 25°C, see(11) −80 −60 −35 −80 −60 −35

Upper threshold

VTHR(MAX) mV

voltage See(11) −95 −60 −25 −95 −60 −25

TJ= 25°C, see(11) −110 −85 −55 −110 −85 −55

Lower threshold

VTHR(MIN) mV

voltage See(11) −160 −85 −40 −160 −85 −40

HYST Hysteresis See(11) 15 15 mV

(7) Connect a 0.1-μF capacitor from the OUT pin to the FEEDBACK pin.

(8) VREF ≤VOUT ≤(VIN −1 V), 2.3 V ≤VIN ≤30 V, 100 μA≤IOUT ≤250 mA.

(9) Two separate tests are performed, one covering 2.5 V ≤VIN ≤VOUT(NOM)) + 1 V and the other test for VOUT(NOM) + 1 V ≤VIN ≤30 V.

(10) VSHUTDOWN ≤1.1 V, VOUT = VOUT(NOM)

(11) Comparator thresholds are expressed in terms of a voltage differential at the FEEDBACK pin below the nominal reference voltage

measured at VIN = VOUT(NOM) + 1 V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain,

which is VOUT / VREF = (R1 + R2) / R2 (see Figure 31).

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Electrical Characteristics: All Voltage Options (continued)

Limits are assured by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods.

Unless otherwise specified, MIN (minimum) and MAX (maximum) specifications in apply over the full Operating Temperature

Range and TYP (typical) values apply at TJ= 25°C, VIN = VOUT(NOM) + 1 V, IOUT = 1 mA, COUT = 2.2 μF for 5-V parts and 4.7

μF for 3.3-V parts. FEEDBACK pin is tied to VTAP pin, OUT pin is tied to SENSE pin.

LP2952AI, LP2953AI, LP2952I, LP2953I,

LP2952AI-3.3, LP2953AI-3.3(1) LP2952I-3.3, LP2953I-3.3

PARAMETER TEST CONDITIONS UNIT

MIN TYP MAX MIN TYP MAX

SHUTDOWN INPUT(12)

TJ= 25°C −7.5 ±3 7.5 −7.5 ±3 7.5

Input offset (Referred to VREF)

VOS mV

voltage −10 10 −10 10

HYST Hysteresis 6 6 mV

TJ= 25°C −30 10 30 −30 10 −30

Input bias VIN(SD) = 0 V to 5 V

IBnA

current VIN(SD) = 0 V to 5 V −50 50 −50 50

AUXILIARY COMPARATOR (LP2953 Only)

TJ= 25°C −7.5 ±3 7.5 −7.5 ±3 7.5

Input offset (Referred to VREF)

VOS mV

voltage (Referred to VREF)−10 ±3 10 −10 ±3 10

HYST Hysteresis 6 6 mV

TJ= 25°C, VIN(COMP) = 0 V to 5 −30 10 30 −30 10 30

Input bias V

IBnA

current VIN(COMP) = 0 V to 5 V −50 10 50 −50 10 50

TJ= 25°C, VOH = 30 V 0.01 1 0.01 1

Output high

IOH μA

leakage VIN(COMP) = 1.3 V 0.01 2 0.01 2

TJ= 25°C, VIN(COMP) = 1.1 V 150 250 150 250

Output low

VOL mV

voltage IOUT(COMP) = 400 μA 150 400 150 400

(12) Drive SHUTDOWN pin with TTL or CMOS-low level to shut regulator OFF, high level to turn regulator ON.

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6.8 Typical Characteristics

Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA= 25°C, VOUT = 5 V.

Figure 1. Quiescent Current Figure 2. Quiescent Current

Figure 4. Ground Pin Current

Figure 3. Ground Pin Current vs Load

Figure 5. Ground Pin Current Figure 6. Output Noise Voltage

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Typical Characteristics (continued)

Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA= 25°C, VOUT = 5 V.

Figure 7. Ripple Rejection Figure 8. Ripple Rejection

Figure 10. Line Transient Response

Figure 9. Ripple Rejection

Figure 11. Line Transient Response Figure 12. Output Impedance

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Typical Characteristics (continued)

Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA= 25°C, VOUT = 5 V.

Figure 13. Load Transient Response Figure 14. Load Transient Response

Figure 16. Enable Transient

Figure 15. Dropout Characteristics

Figure 17. Enable Transient Figure 18. Short-Circuit Output Current and Maximum

Output Current

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Typical Characteristics (continued)

Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA= 25°C, VOUT = 5 V.

Figure 19. Feedback Bias Current Figure 20. FEEDBACK Pin Current

Figure 22. Comparator Sink Current

Figure 21. Error Output

Figure 23. Divider Resistance Figure 24. Dropout Detection Comparator Threshold

Voltages

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Typical Characteristics (continued)

Unless otherwise specified: VIN = 6 V, IOUT = 1 mA, COUT = 2.2 μF, VSD = 3 V, TA= 25°C, VOUT = 5 V.

Figure 25. Thermal Regulation Figure 26. Minimum Operating Voltage

Figure 27. Dropout Voltage

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7 Detailed Description

7.1 Overview

The LP2952 and LP2953 are very high accuracy micropower voltage regulators with low quiescent current (130

μA, typical) and low dropout voltage (typically 60 mV at light loads and 490 mV at 250 mA). They are ideally

suited for use in battery-powered systems.

The LP2952 and LP2953 block diagram contains several features, including:

• Very high accuracy 1.23-V reference.

• Internal protection circuitry, such as thermal foldback current limit, thermal shutdown protection, and reverse

battery-input protection.

• Fixed 5-V and 3.3-V versions.

• Error flag output which may be used for a power-on reset.

• Shutdown input, allowing turn off the regulator when the SHUTDOWN pin is pulled low.

LP2953 versions only:

• An auxiliary comparator is designed for customer special purpose when shutdown is activated, this is a

CMOS- or TTL-compatible output level.

• Automatic output discharge when the SHUTDOWN pin is pulled low.

7.2 Functional Block Diagrams

Figure 28. LP2952 Block Diagram

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Functional Block Diagrams (continued)

Figure 29. LP2953 Block Diagram

7.3 Feature Description

7.3.1 Fixed Voltage Options and Programmable Voltage Version

The LP2952 and LP2953 provide 2 fixed output options: 3.3 V and 5 V. To meet different requirements for the

application, they can also be used as programmable voltage regulators with external resistor networks; see

Application Information for more details.

7.3.2 High-Accuracy Output Voltage

With special and careful design to minimize all contributions to the output voltage error, the LP2952 and LP2953

distinguished themselves as very high output voltage accuracy micropower LDO. This includes a tight initial

tolerance (0.5% typical), extremely good load and line regulation, and a very low output voltage temperature

coefficient, making the part an ideal a low-power voltage reference.

7.3.3 Error Detection Comparator Output

The LP2952 and LP2953 will generate a logic low output when the output falls out of regulation by more than

approximately 5%. See Application Information for more details.

7.3.4 Auxiliary Comparator

An auxiliary comparator is designed for customer special purpose when shutdown is activated. This block is still

active and can be used to generate fault detection, low input line detection signal for system controllers. The

comparator output level is CMOS- or TTL-compatible. See Application Information for more details.

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Feature Description (continued)

7.3.5 Short-Circuit Protection (Current Limit)

The internal current limit circuit is used to protect the LDO against high-load current faults or shorting events. The

LDO is not designed to operate in a steady-state current limit. During a current-limit event, the LDO sources

constant current. Therefore, the output voltage falls when load impedance decreases. Note also that if a current

limit occurs and the resulting output voltage is low, excessive power may be dissipated across the LDO resulting

in a thermal shutdown of the output. A thermal foldback feature limits the short-circuit current to protect the

regulator from damage under all load conditions. If the OUT pin is forced below 0 V before SHUTDOWN goes

high and the load current required exceeds the thermal foldback current limit, the device may not start up

correctly.

7.3.6 Thermal Protection

The device contains a thermal shutdown protection circuit to turn off the output current when excessive heat is

dissipated in the LDO. The thermal time-constant of the semiconductor die is fairly short, and thus the output

cycles on and off at a high rate when thermal shutdown is reached until the power dissipation is reduced. The

internal protection circuitry of the device is designed to protect against thermal overload conditions. The circuitry

is not intended to replace a proper heatsink. Continuously running the device into thermal shutdown degrades its

reliability.

7.3.7 Automatic Output Discharge

Both LP2952 and LP2953 employ an internal 50-mA (typical) pulldown to discharge the output when the

SHUTDOWN pin is low and the output is disabled.

7.4 Device Functional Mode

7.4.1 Shutdown Mode

When pulling the SHUTDOWN pin to low level, the LP2952 and LP2953 will enter shutdown mode, and a very

low quiescent current is consumed. This function is designed for applications which needs a shutdown mode to

effectively enhance battery life cycle. When the SHUTDOWN pin is low the automatic output discharge circuity

will be active. See Application Information for more details.

7.4.2 Operation with 30 V ≥VIN > VOUT(TARGET) +1V

The device operate if the input voltage is equal to, or exceeds, VOUT(TARGET) + 1 V, and SHUTDOWN is pulled to

high level. At input voltages below the minimum VIN requirement, the devices do not operate correctly and output

voltage may not reach target value.

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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

Figure 30. Schematic Diagram

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Application Information (continued)

8.1.1 External Capacitors

A 2.2-μF (or greater) capacitor is required between the OUT pin and ground to assure stability when the output is

set to 5 V. Without this capacitor, the device will oscillate. Most types of tantalum or aluminum electrolytic

capacitors will work here. Film types will work, but are more expensive. Many aluminum electrolytic capacitors

contain electrolytes which freeze at −30°C, which requires the use of solid tantalum capacitors below −25°C. The

important parameters of the capacitor are an equivalent series resistance (ESR) of about 5 Ωor less and a

resonant frequency above 500 kHz (the ESR may increase by a factor of 20 or 30 as the temperature is reduced

from 25°C to −30°C). The value of this capacitor may be increased without limit.

At lower values of output current, less output capacitance is required for stability. The capacitor can be reduced

to 0.68 μF for currents below 10 mA or 0.22 μF for currents below 1 mA.

Programming the output for voltages below 5 V runs the error amplifier at lower gains requiring more output

capacitance for stability. At 3.3-V output, a minimum of 4.7 μF is required. For the worst-case condition of 1.23-V

output and 250 mA of load current, a 6.8-μF (or larger) capacitor should be used.

A 1-μF capacitor should be placed from the IN pin to ground if there is more than 10 inches of wire between the

IN pin and the ac filter capacitor or if a battery input is used.

Stray capacitance to the FEEDBACK pin can cause instability. This problem is most likely to appear when using

high-value external resistors to set the output voltage. Adding a 100-pF capacitor between the OUT and

FEEDBACK pins and increasing the output capacitance to 6.8 μF (or greater) will cure the problem.

8.1.2 Minimum Load

When setting the output voltage using an external resistive divider, a minimum current of 1 μA is recommended

through the resistors to provide a minimum load.

It should be noted that a minimum load current is specified in several of the Electrical Characteristics: All Voltage

Options test conditions, so this value must be used to obtain correlation on these tested limits.

8.1.3 Programming the Output Voltage

The regulator may be pin-strapped for 5-V operation using its internal resistive divider by tying the OUTPUT and

SENSE pins together and also tying the FEEDBACK and VTAP pins together.

Alternatively, it may be programmed for any voltage between the 1.23-V reference and the 30-V maximum rating

using an external pair of resistors (see Figure 31). The complete equation for the output voltage is:

where

• VREF is the 1.23-V reference and IFB is the FEEDBACK pin bias current (−20 nA, typical). (1)

The minimum recommended load current of 1 μA sets an upper limit of 1.2 MΩon the value of R2 in cases

where the regulator must work with no load (see Minimum Load). IFB will produce a typical 2% error in VOUT

which can be eliminated at room temperature by trimming R1. For better accuracy, choosing R2 = 100 kΩwill

reduce this error to 0.17% while increasing the resistor program current to 12 μA. Because the typical quiescent

current is 120 μA, this added current is negligible.

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Application Information (continued)

* See Power Supply Recommendations

** Drive with TTL-low to shutdown

Figure 31. Adjustable Regulator

8.1.4 Dropout Voltage

The dropout voltage of the regulator is defined as the minimum input-to-output voltage differential required for the

output voltage to stay within 100 mV of the output voltage measured with a 1-V differential. The dropout voltage

is independent of the programmed output voltage.

8.1.5 Dropout Detection Comparator

This comparator produces a logic low whenever the output falls out of regulation by more than about 5%. This

value results from the comparator built-in offset of 60 mV divided by the 1.23-V reference (see Functional Block

Diagrams). The 5% low trip level remains constant regardless of the programmed output voltage. An out-of-

regulation condition can result from low input voltage, current limiting, or thermal limiting.

Figure 32 gives a timing diagram showing the relationship between the output voltage, the ERROR output, and

input voltage as the input voltage is ramped up and down to a regulator programmed for 5-V output. The ERROR

signal becomes low at about 1.3-V input. It goes high at about 5-V input, where the output equals 4.75 V.

Because the dropout voltage is load dependent, the input voltage trip points will vary with load current. The

output voltage trip point does not vary.

The comparator has an open-collector output which requires an external pullup resistor. This resistor may be

connected to the regulator output or some other supply voltage. Using the regulator output prevents an invalid

high on the comparator output that occurs if it is pulled up to an external voltage while the regulator input voltage

is reduced below 1.3 V. In selecting a value for the pullup resistor, note that while the output can sink 400 μA,

this current adds to battery drain. Suggested values range from 100 kΩto 1 MΩ. This resistor is not required if

the output is unused.

When VIN ≤1.3 V, the ERROR pin becomes a high impedance, allowing the error flag voltage to rise to its pullup

voltage. Using VOUT as the pullup voltage (rather than an external 5-V source) will keep the error flag voltage

below 1.2 V (typical) in this condition. The user may wish to divide down the error flag voltage using equal-value

resistors (10 kΩis suggested) to ensure a low-level logic signal during any fault condition, while still allowing a

valid logic high level during normal operation.

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Application Information (continued)

* In shutdown mode, ERROR will go high if it has been pulled up to an external supply. To avoid this invalid

response, pull up to regulator output.

** Exact value depends on dropout voltage. (See Power Supply Recommendations)

Figure 32. ERROR Output Timing

8.1.6 Output Isolation

The regulator output can be left connected to an active voltage source (such as a battery) with the regulator input

power shut off, as long as the regulator ground pin is connected to ground. If the ground pin is left floating,

damage to the regulator can occur if the output is pulled up by an external voltage source. If the regulator input

power (VIN) is applied, and the SHUTDOWN pin is low, the automatic output discharge circuit will be active, and

any voltage source applied to the output will be discharged to ground.

8.1.7 Reducing Output Noise

In reference applications it may be advantageous to reduce the ac noise present on the output. One method is to

reduce regulator bandwidth by increasing output capacitance. This is relatively inefficient, because large

increases in capacitance are required to get significant improvement.

Noise can be reduced more effectively by a bypass capacitor placed across R1 (see Figure 31). The formula for

selecting the capacitor to be used is:

(2)

This gives a value of about 0.1 μF. When this is used, the output capacitor must be 6.8 μF (or greater) to

maintain stability. The 0.1-μF capacitor reduces the high-frequency gain of the circuit to unity, lowering the output

noise from 260 μV to 80 μV using a 10-Hz to 100-kHz bandwidth. Also, noise is no longer proportional to the

output voltage, so improvements are more pronounced at high output voltages.

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Application Information (continued)

8.1.8 Auxiliary Comparator (LP2953 Only)

The LP2953 contains an auxiliary comparator whose inverting input is connected to the 1.23-V reference. The

auxiliary comparator has an open-collector output whose electrical characteristics are similar to the dropout

detection comparator. The noninverting input and output are brought out for external connections.

8.1.9 SHUTDOWN Input

A logic-level signal will shut off the regulator output when a low (< 1.2 V) is applied to the SHUTDOWN input.

To prevent possible mis-operation, the SHUTDOWN input must be actively terminated. If the input is driven from

open-collector logic, a pullup resistor (20 kΩto 100 kΩis recommended) should be connected from the

SHUTDOWN input to the regulator input.

If the SHUTDOWN input is driven from a source that actively pulls high and low (like an op-amp), the pullup

resistor is not required, but may be used.

If the shutdown function is not to be used, the cost of the pullup resistor can be saved by simply tying the

SHUTDOWN input directly to the regulator input.

NOTE

Because the Absolute Maximum Ratings state that the SHUTDOWN input can not go

more than 0.3 V below ground, the reverse battery-input protection feature which protects

the regulator input is sacrificed if the SHUTDOWN input is tied directly to the regulator

input.

If reverse-battery input protection is required in an application, the pullup resistor between the SHUTDOWN input

and the regulator input must be used.

8.2 Typical Applications

8.2.1 Basic 5-V Regulator

Figure 33. Basic 5-V Regulator

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Typical Applications (continued)

8.2.1.1 Design Requirements

For this design example, use the parameters listed in Table 1 as the input parameters.

Table 1. Design Parameters

DESIGN PARAMETER DESIGN REQUIREMENT

Input voltage 6 V, ±10%, provided by the DC-DC converter switching at 1 MHz

Output voltage 5 V, ±1%

Output current 250 mA (maximum), 1 mA (minimum)

RMS noise, 10 Hz to 100 kHz 1 mV typical

PSRR at 1 kHz 50 dB typical

8.2.1.2 Detailed Design Procedure

At 150-mA loading, the dropout of the LP2952 and LP2953 has 600-mV maximum dropout over temperature —

thus, a 1500-mV headroom is sufficient for operation over both input and output voltage accuracy. The efficiency

of the LP2952 and LP2953 in this configuration is VOUT / VIN = 83.3%. Input and output capacitors are selected in

accordance with the External Capacitors section. Ceramic capacitances of 1 μF for the input and one 2.2-μF

capacitor for the output are selected. With an efficiency of 83.3% and a 250-mA maximum load, the internal

power dissipation is 250 mW, which corresponds to a 19.2°C junction temperature rise for the SOIC package.

With a VIN – VOUT differential of 1 V and a maximum load current of 250 mA the internal junction temperature (TJ)

of the SOIC package will rise 19.2°C above the ambient temperature. With an 85°C maximum ambient

temperature, the junction temperature is at 104.2°C. To minimize noise, a bypass capacitor of 100 pF is selected

between OUT and FEEDBACK pins.

8.2.1.3 Application Curves

Figure 34. Line Transient Response Figure 35. Load Transient Response

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8.2.2 5-V Current Limiter with Load Fault Indicator

Figure 36 is the example circuit for 5-V current limiter with load fault indicator, it has the following features:

• Output voltage equals +VIN minimum dropout voltage, which varies with output current. Current limits at a

maximum of 380 mA (typical).

• Select R1 so that the comparator input voltage is 1.23 V at the output voltage which corresponds to the

desired fault current value.

Figure 36. 5-V Current Limiter With Load Fault Indicator

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8.2.3 Low Temperature Coefficient Current Sink

The LP2952 or LP2953 can be used as a low drift current source as Figure 37 shows. By connecting VOUT to

FEEDBACK, VOUT will be regulated at 1.235 V, and current consumption at R is IOUT = 1.23/R.

Figure 37. Low Temperature Coefficient Current Sink

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8.2.4 5-V Regulator With Error Flags for Low Battery and Out of Regulation

Figure 38 is the example circuit for 5-V regulator with error flags for low battery and out of regulation, it has the

following features:

• Connect to logic or microprocessor control inputs.

• LOW BATT flag warns the user that the battery has discharged down to about 5.8 V, giving the user time to

recharge the battery or power down some hardware with high power requirements. The output is still in

regulation at this time.

• OUT OF REGULATION flag indicates when the battery is almost completely discharged, and can be used to

initiate a power-down sequence.

Figure 38. 5-V Regulator With Error Flags for Low Battery and Out of Regulation

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8.2.5 5-V Battery Powered Supply With Backup and Low Battery Flag

Figure 39 is the example circuit for 5-V battery powered supply with backup and low battery flag, it has the

following features:

• The circuit switches to the NI-CAD backup battery when the main battery voltage drops below about 5.6 V

and returns to the main battery when its voltage is recharged to about 6 V.

• The 5-V MAIN output powers circuitry which requires no backup, and the 5-V MEMORY output powers critical

circuitry which cannot be allowed to lose power.

• The BATTERY LOW flag goes low whenever the circuit switches to the NI-CAD backup battery.

Figure 39. 5-V Battery Powered Supply With Backup and Low Battery Flag

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8.2.6 5-V Regulator With Timed Power-On Reset

Figure 40 is the circuit designed to generate a adjustable power on reset signal. Adjusting RTand CTvalues

causes a certain delay time as Figure 41 shows.

Figure 40. 5-V Regulator With Timed Power-On Reset

* RT= 1 MΩ, CT= 0.1 μF

Figure 41. Timing Diagram for Timed Power-On Reset

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8.2.7 5-V Regulator With Snap-ON and Snap-OFF Features and Hysteresis

Figure 42 is the circuit designed to generate 5-V regulator with snap-ON and snap-OFF features and hysteresis.

The output turns on at VIN = 5.87 V and turns off at VIN = 5.64 V.

* Turns on at VIN = 5.87 V

Turns off at VIN = 5.64 V

(for component values shown)

Figure 42. 5-V Regulator With Snap-ON and Snap-OFF Features and Hysteresis

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8.2.8 5-V Regulator With Error Flags for Low Battery and Out of Regulation With Snap-ON or Snap-OFF

Output

Figure 43 is the circuit as 5-V regulator with error flags for low battery and out of regulation with Snap-ON/Snap-

OFF output. It has the following features:

• Connect to logic or microprocessor control inputs.

• LOW BATT flag warns the user that the battery has discharged down to about 5.8 V, giving the user time to

recharge the battery or shutdown hardware with high power requirements. The output is still in regulation at

this time.

• OUT OF REGULATION flag goes low if the output goes below about 4.7 V, which could occur from a load

fault.

• OUTPUT has Snap-ON or Snap-OFF feature. Regulator snaps ON at about 5.7-V input, and OFF at about

5.6 V.

Figure 43. 5-V Regulator With Error Flags for Low Battery and Out of Regulation With Snap-ON or Snap-

OFF Output

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8.2.9 5-V Regulator With Timed Power-On Reset, Snap-ON and Snap-OFF Features, and Hysteresis

Figure 44 is the circuit designed for 5-V regulator with timed power-on reset, Snap-ON and Snap-OFF features,

and hysteresis. Its timing diagram shows as Figure 45.

Figure 44. 5-V Regulator With Timed Power-On Reset, Snap-ON or Snap-OFF Feature, and Hysteresis

td= (0.28), RC = 28 ms for components shown.

Figure 45. Timing Diagram

9 Power Supply Recommendations

The LP2952 and LP2953 is designed to operate from an input voltage supply range between 2.3 V and 30 V.

The input voltage range provides adequate headroom in order for the device to have a regulated output, normally

VIN should be 1 V higher than output voltage to provide a sufficient headroom. This input supply must be well

regulated. If the input supply is noisy, additional input capacitors with low ESR can help improve the output noise

performance.

Maximum VIN should never be higher than 30 V. Input voltage beyond 30 V may trigger EOS and cause

permanent damage to the device.

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Ground

VOUT

VIN

Input

Capacitor

Output

Capacitor

GND

OUT

SENSE VTAP

GROUND

FEEDBACK

Error Pullup

Resistor

Vout

SHUTDOWN

ERROR

GROUND GROUND

REFERENCE

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10 Layout

10.1 Layout Guidelines

For best overall performance, place all circuit components on the same side of the circuit board and as near as

practical to the respective LDO pin connections. Place ground return connections to the input and output

capacitors, and to the LDO ground pin as close to each other as possible, connected by a wide, component-side,

copper surface. The use of vias and long traces to create LDO circuit connections is strongly discouraged and

negatively affects system performance. This grounding and layout scheme minimizes inductive parasitics, and

thereby reduces load-current transients, minimizes noise, and increases circuit stability.

A ground reference plane is also recommended and is either embedded in the PCB itself or located on the

bottom side of the PCB opposite the components. This reference plane serves to assure accuracy of the output

voltage, shield noise, and behaves similar to a thermal plane to spread (or sink) heat from the LDO device. In

most applications, this ground plane is necessary to meet thermal requirements.

10.2 Layout Example

Figure 46. Layout Schematic

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10.3 Power Dissipation: Heatsink Requirements (Industrial Temperature Range Devices)

The maximum allowable power dissipation for the LP2952 or LP2953 is limited by the maximum operating

junction temperature (125°C) and the external factors that determine how quickly heat flows away from the part:

the ambient temperature and the junction-to-ambient thermal resistance (RθJA) for the specific application.

The industrial temperature range (−40°C ≤TJ≤125°C) parts are manufactured in PDIP and surface-mount

packages which contain a copper lead frame that allows heat to be effectively conducted away from the die,

through the ground pins of the IC, and into the copper of the PC board. Details on heatsinking using PC board

copper are covered later.

Figure 47. Power Dissipation vs Ambient Temperature

for RθJA = 95°C/W

To determine if a heatsink is required, the maximum power dissipated by the regulator, P(MAX), must be

calculated. It is important to remember that if the regulator is powered from a transformer connected to the AC

line, the maximum specified AC input voltage must be used (because this produces the maximum DC input

voltage to the regulator). Figure 48 shows the voltages and currents which are present in the circuit. The formula

for calculating the power dissipated in the regulator is also shown in Figure 48:

Figure 48. PTOTAL = (VIN −VOUT) IOUT + (VIN) IG

Current/Voltage Diagram

The next parameter which must be calculated is the maximum allowable temperature rise, TR(MAX). This is

calculated by using the formula:

TR(MAX) = TJ(MAX) −TA(MAX) = RθJA × P(MAX)

where:

• TJ(MAX) is the maximum allowable junction temperature

• TA(MAX) is the maximum ambient temperature (3)

Using the calculated values for TR(MAX) and P(MAX), the required value for junction-to-ambient thermal resistance,

RθJA, can now be found.

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Power Dissipation: Heatsink Requirements (Industrial Temperature Range Devices) (continued)

The heatsink is made using the PC board copper. The heat is conducted from the die, through the lead frame

(inside the part), and out the pins which are soldered to the PC board. The pins used for heat conduction are

given in Table 2.

Table 2. Heat Conducting Pins

PART PACKAGE PINS

LP2953IN, LP2953AIN 16-pin PDIP 4, 5, 12, 13

LP2953IN-3.3, LP2953AIN-3.3

LP2952IM, LP2952AIM

LP2952IM-3.3, LP2952AIM-3.3 16-pin surface mount (SOIC) 1, 8, 9, 16

LP2953IM, LP2953AIM

LP2953IM-3.3, LP2953AIM-3.3

Figure 49 shows copper patterns which may be used to dissipate heat from the LP2952 and LP2953.

* For best results, use L = 2H.

** 14-Pin PDIP is similar, see Table 2 for pins designated for heatsinking.

Figure 49. Copper Heatsink Patterns

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11 Device and Documentation Support

11.1 Related Links

Table 3 lists quick access links. Categories include technical documents, support and community resources,

tools and software, and quick access to sample or buy.

Table 3. Related Links

TECHNICAL TOOLS & SUPPORT &

PARTS PRODUCT FOLDER SAMPLE & BUY DOCUMENTS SOFTWARE COMMUNITY

LP2952-N Click here Click here Click here Click here Click here

LP2952A Click here Click here Click here Click here Click here

LP2953 Click here Click here Click here Click here Click here

LP2953A Click here Click here Click here Click here Click here

11.2 Trademarks

All trademarks are the property of their respective owners.

11.3 Electrostatic Discharge Caution

These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam

during storage or handling to prevent electrostatic damage to the MOS gates.

11.4 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.

Product Folder Links: LP2952-N LP2952A LP2953 LP2953A

PACKAGE OPTION ADDENDUM

www.ti.com 30-Jul-2018

Addendum-Page 1

PACKAGING INFORMATION

Orderable Device Status

(1)

Package Type Package

Drawing Pins Package

Qty Eco Plan

(2)

Lead/Ball Finish

(6)

MSL Peak Temp

(3)

Op Temp (°C) Device Marking

(4/5)

Samples

LP2952AIM NRND SOIC D 16 48 TBD Call TI Call TI -40 to 125 LP2952AIM

LP2952AIM/NOPB ACTIVE SOIC D 16 48 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2952AIM

LP2952AIMX/NOPB ACTIVE SOIC D 16 2500 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2952AIM

LP2952IM NRND SOIC D 16 48 TBD Call TI Call TI -40 to 125 LP2952IM

LP2952IM/NOPB ACTIVE SOIC D 16 48 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2952IM

LP2952IMX/NOPB ACTIVE SOIC D 16 2500 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2952IM

LP2953AIM/NOPB ACTIVE SOIC D 16 48 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2953AIM

LP2953AIMX/NOPB ACTIVE SOIC D 16 2500 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2953AIM

LP2953IM NRND SOIC D 16 48 TBD Call TI Call TI -40 to 125 LP2953IM

LP2953IM/NOPB ACTIVE SOIC D 16 48 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2953IM

LP2953IMX/NOPB ACTIVE SOIC D 16 2500 Green (RoHS

& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LP2953IM

(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.

PACKAGE OPTION ADDENDUM

www.ti.com 30-Jul-2018

Addendum-Page 2

(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/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish 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.

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

LP2952AIMX/NOPB SOIC D 16 2500 330.0 16.4 6.5 10.3 2.3 8.0 16.0 Q1

LP2952IMX/NOPB SOIC D 16 2500 330.0 16.4 6.5 10.3 2.3 8.0 16.0 Q1

LP2953AIMX/NOPB SOIC D 16 2500 330.0 16.4 6.5 10.3 2.3 8.0 16.0 Q1

LP2953IMX/NOPB SOIC D 16 2500 330.0 16.4 6.5 10.3 2.3 8.0 16.0 Q1

PACKAGE MATERIALS INFORMATION

www.ti.com 8-Oct-2016

Pack Materials-Page 1

*All dimensions are nominal

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

LP2952AIMX/NOPB SOIC D 16 2500 367.0 367.0 35.0

LP2952IMX/NOPB SOIC D 16 2500 367.0 367.0 35.0

LP2953AIMX/NOPB SOIC D 16 2500 367.0 367.0 35.0

LP2953IMX/NOPB SOIC D 16 2500 367.0 367.0 35.0

PACKAGE MATERIALS INFORMATION

www.ti.com 8-Oct-2016

Pack Materials-Page 2

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LP2953AMGW-QMLV LP2953 MDS 5962-9233602VXA