LM2585T-5.0/NOPB - NATIONAL SEMICONDUCTOR

Product

Folder

Order

Now

Technical

Documents

Tools &

Software

Support &

Community

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.

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

LM2585 4-V to 40-V, 3-A Step-Up Wide V

Flyback Converter

1 Features

1• Requires Few External Components

• Family of Standard Inductors and Transformers

• NPN Output Switches 3 A, Can Stand Off 65 V

• Wide Input Voltage Range: 4 V to 40 V

• Current-mode Operation for Improved Transient

Response, Line Regulation, and Current Limit

• 100-kHz Switching Frequency

• Internal Soft-Start Function Reduces In-rush

Current During Start-up

• Output Transistor Protected by Current Limit,

Undervoltage Lockout, and Thermal Shutdown

• System Output Voltage Tolerance of ±4%

Maximum Over Line and Load Conditions

• Create a Custom Design Using the LM2585 With

the WEBENCH®Power Designer

2 Applications

• Flyback Regulator

• Multiple-output Regulator

• Simple Boost Regulator

• Forward Converter

3 Description

The LM2585 series of regulators are monolithic

integrated circuits specifically designed for flyback,

step-up (boost), and forward converter applications.

The device is available in 4 different output voltage

versions: 3.3 V, 5 V, 12 V, and adjustable.

Requiring a minimum number of external

components, these regulators are cost effective and

simple to use. Included in the datasheet are typical

circuits of boost and flyback regulators. Also listed

are selector guides for diodes and capacitors and a

family of standard inductors and flyback transformers

designed to work with these switching regulators.

The power switch is a 3-A NPN device that can stand

off 65 V. Protecting the power switch are current and

thermal limiting circuits, and an undervoltage lockout

circuit. This IC contains a 100-kHz fixed-frequency

internal oscillator that permits the use of small

magnetics. Other features include soft start mode to

reduce in-rush current during start-up, current mode

control for improved rejection of input voltage and

output load transients and cycle-by-cycle current

limiting. An output voltage tolerance of ±4%, within

specified input voltages and output load conditions, is

specified for the power supply system.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)

LM2585 DDPAK/ TO-263 (5) 10.16 mm × 8.42 mm

TO-220 (5) 14.986 mm × 10.16 mm

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

the end of the data sheet.

12-V Flyback Regulator Design Example

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Table of Contents

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

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

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

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

5 Pin Configurations................................................. 3

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

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

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

6.3 Recommended Operating Ratings............................ 4

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

6.5 Electrical Characteristics: 3.3 V ............................... 5

6.6 Electrical Characteristics: 5 V .................................. 6

6.7 Electrical Characteristics: 12-V ................................ 6

6.8 Electrical Characteristics: Adjustable........................ 7

6.9 Electrical Characteristics: All Versions ..................... 8

6.10 Typical Characteristics............................................ 9

7 Detailed Description............................................ 11

7.1 Overview................................................................. 11

7.2 Functional Block Diagram....................................... 13

7.3 Feature Description................................................. 13

8 Application and Implementation ........................ 15

8.1 Application Information............................................ 15

8.2 Typical Applications ................................................ 15

8.3 Additional Application Examples............................. 27

9 Layout................................................................... 29

9.1 Layout Guidelines ................................................... 29

9.2 Heat Sink/Thermal Considerations ......................... 29

10 Device and Documentation Support ................. 31

10.1 Device Support...................................................... 31

10.2 Receiving Notification of Documentation Updates 31

10.3 Community Resources.......................................... 31

10.4 Trademarks........................................................... 31

10.5 Electrostatic Discharge Caution............................ 31

10.6 Glossary................................................................ 32

11 Mechanical, Packaging, and Orderable

Information........................................................... 32

4 Revision History

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

Changes from Revision F (April 2013) to Revision G Page

• Editorial changes only, no technical revisions; add links for WEBENCH .............................................................................. 1

Changes from Revision E (April 2013) to Revision F Page

• Changed layout of National Semiconductor data sheet to TI format.................................................................................... 30

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

5 Pin Configurations

NDH Package

5-Pin TO-220

Top View

KTT Package

5-Pin DDPAK/TO-263

Top View

NDH Package

5-Pin TO-220

Side View

KTT Package

5-Pin DDPAK/TO-263

Side View

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating ratings indicate conditions the

device is intended to be functional, but device parameter specifications may not be specified under these conditions. For specifications

and test conditions see Electrical Characteristics: All Versions .

(2) If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office/ Distributors for availability and

specifications.

(3) Note that switch current and output current are not identical in a step-up regulator. Output current cannot be internally limited when the

LM2585 is used as a step-up regulator. To prevent damage to the switch, the output current must be externally limited to 3 A. However,

output current is internally limited when the LM2585 is used as a flyback regulator (see Typical Flyback Regulator Applications for more

information).

(4) The junction temperature of the device (TJ) is a function of the ambient temperature (TA), the junction-to-ambient thermal resistance

(θJA), and the power dissipation of the device (PD). A thermal shutdown will occur if the temperature exceeds the maximum junction

temperature of the device: PD×θJA + TA(MAX) ≥TJ(MAX). For a safe thermal design, check that the maximum power dissipated by the

device is less than: PD≤[TJ(MAX) −TA(MAX))]/θJA. When calculating the maximum allowable power dissipation, derate the maximum

junction temperature—this ensures a margin of safety in the thermal design.

6 Specifications

6.1 Absolute Maximum Ratings

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

Input Voltage −0.4 V ≤VIN ≤45 V

Switch Voltage −0.4 V ≤VSW ≤65 V

Switch Current (3) Internally Limited

Compensation Pin Voltage −0.4 V ≤VCOMP ≤2.4 V

Feedback Pin Voltage −0.4 V ≤VFB ≤2 V

Storage Temperature Range −65°C to +150°C

Lead Temperature (Soldering, 10 sec.) 260°C

Maximum Junction Temperature(4) 150°C

Power Dissipation (4) Internally Limited

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

6.2 ESD Ratings VALUE UNIT

V(ESD) Electrostatic discharge

(minimum) Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)

(C = 100 pF, R = 1.5 kΩ)2000 V

6.3 Recommended Operating Ratings

Supply Voltage 4 V ≤VIN ≤40 V

Output Switch Voltage 0 V ≤VSW ≤60 V

Output Switch Current ISW ≤3 A

Junction Temperature Range −40°C ≤TJ≤+125°C

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

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

report.

(2) Junction-to-ambient thermal resistance for the 5-lead TO-263 mounted horizontally against a PC board area of 0.136 square inches (the

same size as the DDPAK/TO-263 package) of 1 oz. (0.0014 in. thick) copper.

(3) Junction-to-ambient thermal resistance (no external heat sink) for the 5-lead TO-220 package mounted vertically, with ½ inch leads in a

socket, or on a PC board with minimum copper area.

(4) Junction-to-ambient thermal resistance for the 5-lead TO-263 mounted horizontally against a PC board area of 0.4896 square inches

(3.6 times the area of the DDPAK/TO-263 package) of 1 oz. (0.0014 in. thick) copper.

(5) Junction-to-ambient thermal resistance (no external heat sink) for the 5-lead TO-220 package mounted vertically, with ½ inch leads

soldered to a PC board containing approximately 4 square inches of (1 oz.) copper area surrounding the leads.

(6) Junction-to-ambient thermal resistance for the 5-lead TO-263 mounted horizontally against a PC board copper area of 1.0064 square

inches (7.4 times the area of the DDPAK/TO-2633 package) of 1 oz. (0.0014 in. thick) copper. Additional copper area reduces thermal

resistance further.

6.4 Thermal Information

THERMAL METRIC(1) LM2585

UNITKTT (DDPAK/TO-263 NDH (TO-220)

5 PINS 5 PINS

RθJA Junction-to-ambient thermal resistance 56(2) 65(3)

°C/W35(4) 45(5)

26(6) —

RθJC Junction-to-case thermal resistance 2 2 °C/W

(1) External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the

LM2585 is used as shown in Figure 47 and Figure 48, system performance will be as specified by the system parameters.

(2) All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using

standard Statistical Quality Control (SQC) methods.

(3) A 1-MΩresistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.

6.5 Electrical Characteristics: 3.3 V

Specifications with standard type face are for TJ= 25°C, and those in bold type face apply over full Operating Temperature

Range. Unless otherwise specified, VIN = 5V.

PARAMETER TEST CONDITIONS TYP MIN MAX UNIT

SYSTEM PARAMETERS Test Circuit of Figure 47 (1)

VOUT Output Voltage VIN = 4V to 12V 3.3 3.17/3.14 3.43/3.46 V

ILOAD = 0.3A to 1.2A

ΔVOUT/ Line Regulation VIN = 4V to 12V 20 50/100 mV

ΔVIN ILOAD = 0.3A

ΔVOUT/ Load Regulation VIN = 12V 20 50/100 mV

ΔILOAD ILOAD = 0.3A to 1.2A

ηEfficiency VIN = 5V, ILOAD = 0.3A 76%

UNIQUE DEVICE PARAMETERS (2)

VREF Output Reference Measured at Feedback Pin 3.3 3.242/3.234 3.358/3.366 V

Voltage VCOMP = 1.0V

ΔVREF Reference Voltage VIN = 4V to 40V 2.0 mV

Line Regulation

GMError Amp ICOMP =−30 μA to +30 μA 1.193 0.678 2.259 mmho

Transconductance VCOMP = 1.0V

AVOL Error Amp VCOMP = 0.5V to 1.6V 260 151/75 V/V

Voltage Gain RCOMP = 1.0 MΩ(3)

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

(1) External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the

LM2585 is used as shown in Figure 47 and Figure 48, system performance will be as specified by the system parameters.

(2) All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using

standard Statistical Quality Control (SQC) methods.

(3) A 1-MΩresistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.

6.6 Electrical Characteristics: 5 V

PARAMETER TEST CONDITIONS TYP MIN MAX UNIT

SYSTEM PARAMETERS Test Circuit of Figure 47 (1)

VOUT Output Voltage VIN = 4V to 12V 5.0 4.80/4.75 5.20/5.25 V

ILOAD = 0.3A to 1.1A

ΔVOUT/ Line Regulation VIN = 4V to 12V 20 50/100 mV

ΔVIN ILOAD = 0.3A

ΔVOUT/ Load Regulation VIN = 12V 20 50/100 mV

ΔILOAD ILOAD = 0.3A to 1.1A

ηEfficiency VIN = 12V, ILOAD = 0.6A 80 %

UNIQUE DEVICE PARAMETERS (2)

VREF Output Reference Measured at Feedback Pin 5.0 4.913/4.900 5.088/5.100 V

Voltage VCOMP = 1.0V

ΔVREF Reference Voltage VIN = 4V to 40V 3.3 mV

Line Regulation

GMError Amp ICOMP =−30 μA to +30 μA 0.750 0.447 1.491 mmho

Transconductance VCOMP = 1.0V

AVOL Error Amp VCOMP = 0.5V to 1.6V 165 99/49 V/V

Voltage Gain RCOMP = 1.0 MΩ(3)

(1) External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the

LM2585 is used as shown in Figure 47 and Figure 48, system performance will be as specified by the system parameters.

(2) All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using

standard Statistical Quality Control (SQC) methods.

(3) A 1-MΩresistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.

6.7 Electrical Characteristics: 12-V

PARAMETER TEST CONDITIONS TYP MIN MAX UNIT

SYSTEM PARAMETERS Test Circuit of Figure 48 (1)

VOUT Output Voltage VIN = 4V to 10V 12.0 11.52/11.40 12.48/12.60 V

ILOAD = 0.2A to 0.8A

ΔVOUT/ Line Regulation VIN = 4V to 10V 20 100/200 mV

ΔVIN ILOAD = 0.2A

ΔVOUT/ Load Regulation VIN = 10V 20 100/200 mV

ΔILOAD ILOAD = 0.2A to 0.8A

ηEfficiency VIN = 10V, ILOAD = 0.6A 93%

UNIQUE DEVICE PARAMETERS (2)

VREF Output Reference Measured at Feedback Pin 12.0 11.79/11.76 12.21/12.24 V

Voltage VCOMP = 1.0V

ΔVREF Reference Voltage VIN = 4V to 40V 7.8 mV

Line Regulation

GMError Amp ICOMP =−30 μA to +30 μA 0.328 0.186 0.621 mmho

Transconductance VCOMP = 1.0V

AVOL Error Amp VCOMP = 0.5V to 1.6V 70 41/21 V/V

Voltage Gain RCOMP = 1.0 MΩ(3)

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

(1) External components such as the diode, inductor, input and output capacitors can affect switching regulator performance. When the

LM2585 is used as shown in Figure 47 and Figure 48, system performance will be as specified by the system parameters.

(2) All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using

standard Statistical Quality Control (SQC) methods.

(3) A 1-MΩresistor is connected to the compensation pin (which is the error amplifier output) to ensure accuracy in measuring AVOL.

6.8 Electrical Characteristics: Adjustable

PARAMETER TEST CONDITIONS TYP MIN MAX UNIT

SYSTEM PARAMETERS Test Circuit of Figure 48 (1)

VOUT Output Voltage VIN = 4V to 10V 12.0 11.52/11.40 12.48/12.60 V

ILOAD = 0.2A to 0.8A

ΔVOUT/ Line Regulation VIN = 4V to 10V 20 100/200 mV

ΔVIN ILOAD = 0.2A

ΔVOUT/ Load Regulation VIN = 10V 20 100/200 mV

ΔILOAD ILOAD = 0.2A to 0.8A

ηEfficiency VIN = 10V, ILOAD = 0.6A 93%

UNIQUE DEVICE PARAMETERS (2)

VREF Output Reference Measured at Feedback Pin 1.230 1.208/1.205 1.252/1.255 V

Voltage VCOMP = 1.0V

ΔVREF Reference Voltage VIN = 4V to 40V 1.5 mV

Line Regulation

GMError Amp ICOMP =−30 μA to +30 μA 3.200 1.800 6.000 mmho

Transconductance VCOMP = 1.0V

AVOL Error Amp VCOMP = 0.5V to 1.6V 670 400/200 V/V

Voltage Gain RCOMP = 1.0 MΩ(3)

IBError Amp VCOMP = 1.0V 125 425/600 nA

Input Bias Current

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

(1) All room temperature limits are 100% production tested, and all limits at temperature extremes are specified via correlation using

standard Statistical Quality Control (SQC) methods.

(2) To measure this parameter, the feedback voltage is set to a high value, depending on the output version of the device, to force the error

amplifier output low. Adj: VFB = 1.41 V; 3.3 V: VFB = 3.8 V; 5 V: VFB = 5.75 V; 12 V: VFB = 13.8 V.

(3) To measure this parameter, the feedback voltage is set to a low value, depending on the output version of the device, to force the error

amplifier output high. Adj: VFB = 1.05 V; 3.3 V: VFB = 2.81 V; 5 V: VFB = 4.25 V; 12 V: VFB = 10.2 V.

(4) To measure the worst-case error amplifier output current, the LM2585 is tested with the feedback voltage set to its low value (specified

in Tablenote 3) and at its high value (specified in Tablenote 2).

6.9 Electrical Characteristics: All Versions

PARAMETER TEST CONDITIONS TYP MIN MAX UNIT

COMMON DEVICE PARAMETERS for all versions (1)

ISInput Supply Current (Switch Off)(2) 11 15.5/16.5 mA

ISWITCH = 1.8A 50 100/115 mA

VUV Input Supply

Undervoltage Lockout RLOAD = 100Ω3.30 3.05 3.75 V

fOOscillator Frequency Measured at Switch Pin

RLOAD = 100Ω100 85/75 115/125 kHz

VCOMP = 1.0V

fSC Short-Circuit

Frequency Measured at Switch Pin

RLOAD = 100Ω25 kHz

VFEEDBACK = 1.15V

VEAO Error Amplifier

Output Swing Upper Limit(3) 2.8 2.6/2.4 V

Lower Limit(2) 0.25 0.40/0.55 V

IEAO Error Amp

Output Current

(Source or Sink)

See (4) 165 110/70 260/320 μA

ISS Soft Start Current VFEEDBACK = 0.92V 11.0 8.0/7.0 17.0/19.0 μA

VCOMP = 1.0V

D Maximum Duty

Cycle RLOAD = 100Ω(3) 98 93/90 %

ILSwitch Leakage

Current Switch Off 15 300/600 μA

VSWITCH = 60V

VSUS Switch Sustaining

Voltage dV/dT = 1.5V/ns 65 V

VSAT Switch Saturation

Voltage ISWITCH = 3.0A 0.45 0.65/0.9 V

ICL NPN Switch

Current Limit 43 7.0 A

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

6.10 Typical Characteristics

Figure 1. Supply Current vs Temperature Figure 2. Reference Voltage vs Temperature

Figure 3. ΔReference Voltage vs Supply Voltage Figure 4. Current Limit vs Temperature

Figure 5. Feedback Pin Bias Current vs Temperature Figure 6. Switch Saturation Voltage vs Temperature

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Typical Characteristics (continued)

Figure 7. Switch Transconductance vs Temperature Figure 8. Oscillator Frequency vs Temperature

Figure 9. Error Amp Transconductance vs Temperature Figure 10. Error Amp Voltage Gain vs Temperature

Figure 11. Short Circuit Frequency vs Temperature

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

7 Detailed Description

7.1 Overview

The LM2585 is ideally suited for use in the flyback regulator topology. The flyback regulator can produce a single

output voltage, such as the one shown in Figure 12, or multiple output voltages. In Figure 12, the flyback

regulator generates an output voltage that is inside the range of the input voltage. This feature is unique to

flyback regulators and cannot be duplicated with buck or boost regulators.

The operation of a flyback regulator is as follows (refer to Figure 12): when the switch is on, current flows

through the primary winding of the transformer, T1, storing energy in the magnetic field of the transformer. Note

that the primary and secondary windings are out of phase, so no current flows through the secondary when

current flows through the primary. When the switch turns off, the magnetic field collapses, reversing the voltage

polarity of the primary and secondary windings. Now rectifier D1 is forward biased and current flows through it,

releasing the energy stored in the transformer. This produces voltage at the output.

The output voltage is controlled by modulating the peak switch current. This is done by feeding back a portion of

the output voltage to the error amp, which amplifies the difference between the feedback voltage and a 1.23-V

reference. The error amp output voltage is compared to a ramp voltage proportional to the switch current (in

other words, inductor current during the switch on time). The comparator terminates the switch on time when the

two voltages are equal, thereby controlling the peak switch current to maintain a constant output voltage.

Figure 12. 12-V Flyback Regulator Design Example

As shown in Figure 12, the LM2585 can be used as a flyback regulator by using a minimum number of external

components. The switching waveforms of this regulator are shown in Figure 13. Typical characteristics observed

during the operation of this circuit are shown in Figure 14.

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Overview (continued)

A: Switch Voltage, 20 V/div

B: Switch Current, 2 A/div

C: Output Rectifier Current, 2 A/div

D: Output Ripple Voltage, 50 mV/div

AC-Coupled

Horizontal: 2 μs/div

Figure 13. Switching Waveforms

Figure 14. VOUT Load Current Step Response

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

7.2 Functional Block Diagram

For Fixed Versions

3.3V, R1 = 3.4k, R2 = 2k

5V, R1 = 6.15k, R2 = 2k

12V, R1 = 8.73k, R2 = 1k

For Adj. Version

R1 = Short (0Ω), R2 = Open

7.3 Feature Description

7.3.1 Step-Up (Boost) Regulator Operation

Figure 15 shows the LM2585 used as a step-up (boost) regulator. This is a switching regulator that produces an

output voltage greater than the input supply voltage.

A brief explanation of how the LM2585 boost regulator works is as follows (refer to Figure 15). When the NPN

switch turns on, the inductor current ramps up at the rate of VIN/L, storing energy in the inductor. When the

switch turns off, the lower end of the inductor flies above VIN, discharging its current through diode (D) into the

output capacitor (COUT) at a rate of (VOUT −VIN)/L. Thus, energy stored in the inductor during the switch on time

is transferred to the output during the switch off time. The output voltage is controlled by adjusting the peak

switch current, as described in .

Figure 15. 12-V Boost Regulator

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Feature Description (continued)

By adding a small number of external components (as shown in Figure 15), the LM2585 can be used to produce

a regulated output voltage that is greater than the applied input voltage. The switching waveforms observed

during the operation of this circuit are shown in Figure 16. Typical performance of this regulator is shown in

Figure 17.

A: Switch Voltage, 10 V/div

B: Switch Current, 2 A/div

C: Inductor Current, 2 A/div

D: Output Ripple Voltage,

100 mV/div, AC-Coupled

Horizontal: 2 μs/div

Figure 16. Switching Waveforms

Figure 17. VOUT Response To Load Current Step

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

8 Application and Implementation

8.1 Application Information

The LM2585 series of regulators are monolithic integrated circuits specifically designed for flyback, step-up

(boost), and forward converter applications. Requiring a minimum number of external components, these

regulators are cost effective and simple to use.

8.2 Typical Applications

8.2.1 Typical Boost Regulator Applications

Figure 18 through Figure 21 show four typical boost applications)—one fixed and three using the adjustable

version of the LM2585. Each drawing contains the part number(s) and manufacturer(s) for every component. For

the fixed 12-V output application, the part numbers and manufacturers' names for the inductor are listed in

Table 3. For applications with different output voltages, refer to the Switchers Made Simple software.

Figure 18. 5-V to 12-V Boost Regulator

Figure 19. 12-V to 24-V Boost Regulator

Figure 20. 24-V to 36-V Boost Regulator

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Typical Applications (continued)

*The LM2585 will require a heat sink in these applications. The size of the heat sink will depend on the maximum

ambient temperature. To calculate the thermal resistance of the IC and the size of the heat sink needed, see Heat

Sink/Thermal Considerations

Figure 21. 24-V to 48-V Boost Regulator

8.2.2 Typical Flyback Regulator Applications

Figure 22 through Figure 27 show six typical flyback applications, varying from single output to triple output. Each

drawing contains the part number(s) and manufacturer(s) for every component except the transformer. For the

transformer part numbers and manufacturers names, the table in Table 1.

Figure 22. Single-Output Flyback Regulator

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

Typical Applications (continued)

Figure 23. Single-Output Flyback Regulator

Figure 24. Single-Output Flyback Regulator

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Typical Applications (continued)

Figure 25. Dual-Output Flyback Regulator

Figure 26. Dual-Output Flyback Regulator

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

Typical Applications (continued)

Figure 27. Triple-Output Flyback Regulator

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Typical Applications (continued)

8.2.2.1 Transformer Selection (T)

Table 1 lists the standard transformers available for flyback regulator applications. Included in the table are the

turns ratio(s) for each transformer, as well as the output voltages, input voltage ranges, and the maximum load

currents for each circuit.

Table 1. Transformer Selection Table

Applications Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27

Transformers T7 T7 T7 T6 T6 T5

VIN 4V–6V 4V–6V 8V–16V 4V–6V 18V–36V 18V–36V

VOUT1 3.3V 5V 12V 12V 12V 5V

IOUT1 (Max) 1.4A 1A 0.8A 0.15A 0.6A 1.8A

N11 1 1 1.2 1.2 0.5

VOUT2 −12V −12V 12V

IOUT2 (Max) 0.15A 0.6A 0.25A

N21.2 1.2 1.15

VOUT3 −12V

IOUT3 (Max) 0.25A

N31.15

(1) Coilcraft Inc. Phone: (800) 322-2645 www.coilcraft.com

(2) Pulse Engineering Inc. Phone: (619) 674-8100 www.digikey.com

(3) Renco Electronics Inc. Phone: (800) 645-5828 www.cdiweb.com/renco

(4) Schott Corp. Phone: (612) 475-1173 www.schottcorp.com/

Table 2. Transformer Manufacturer Guide

Transform

er Type

Manufacturers' Part Numbers

Coilcraft

(1) Coilcraft

(1)

Surface Mount

Pulse

(2)

Surface Mount

Pulse

(2) Renco

(3) Schott

(4)

T5 Q4338-B Q4437-B PE-68413 — RL-5532 67140890

T6 Q4339-B Q4438-B PE-68414 — RL-5533 67140900

T7 S6000-A S6057-A — PE-68482 RL-5751 26606

8.2.2.2 Transformer Footprints

Figure 28 through Figure 42 show the footprints of each transformer, listed in Table 1.

Figure 28. Coilcraft S6000-A (Top View) Figure 29. Coilcraft Q4339-B (Top View)

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

Figure 30. Coilcraft Q4437-B (Top View)

(Surface Mount) Figure 31. Coilcraft Q4338-B

(Top View)

Figure 32. Coilcraft S6057-A (Top View)

(Surface Mount) Figure 33. Coilcraft Q4438-B (Top View)

(Surface Mount)

Figure 34. Pulse PE-68482 (Top View) Figure 35. Pulse Pe-68414 (Top View)

(Surface Mount)

Figure 36. Pulse PE-68413 (Top View)

(Surface Mount) Figure 37. Renco Rl-5751 (Top View)

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Figure 38. Renco Rl-5533

(Top View) Figure 39. Renco Rl-5532 (Top View)

Figure 40. Schott 26606 (Top View) Figure 41. Schott 67140900 (Top View)

Figure 42. Schott 67140890

(Top View)

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

(1) Coilcraft Inc. Phone: (800) 322-2645 1102 Silver Lake Road, Cary, IL 60013 Fax: (708) 639-1469

(2) Pulse Engineering Inc. Phone: (619) 674-8100 12220 World Trade Drive, San Diego, CA 92128 Fax: (619) 674-8262

(3) Renco Electronics Inc. Phone (800) 645-5828 60 Jeffryn Blvd. East, Deer Park, NY 11729 Fax: (516) 586-5562

(4) Schott Corp. Phone: (612) 475-1173 1000 Parkers Lane Road, Wayzata, MN 55391 Fax: (612) 475-1786

8.2.3 Design Requirements

Table 3 contains a table of standard inductors, by part number and corresponding manufacturer, for the fixed

output regulator of Figure 18.

Table 3. Inductor Selection Table

Coilcraft(1) Pulse(2) Renco(3) Schott(4) Schott (Surface Mount)(4)

D03316-153 PE-53898 RL-5471-7 67146510 67146540

8.2.4 Detailed Design Procedure

8.2.4.1 Custom Design With WEBENCH® Tools

Click here to create a custom design using the LM2585 device with the WEBENCH® Power Designer.

1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.

2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.

3. Compare the generated design with other possible solutions from Texas Instruments.

The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time

pricing and component availability.

In most cases, these actions are available:

• Run electrical simulations to see important waveforms and circuit performance

• Run thermal simulations to understand board thermal performance

• Export customized schematic and layout into popular CAD formats

• Print PDF reports for the design, and share the design with colleagues

Get more information about WEBENCH tools at www.ti.com/WEBENCH.

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

8.2.4.2 Programming Output Voltage (Selecting R1And R2)

Referring to the adjustable regulator in Figure 50, the output voltage is programmed by the resistors R1and R2

by the following formula:

VOUT = VREF (1 + R1/R2)

where

• VREF = 1.23 V (1)

Resistors R1and R2divide the output voltage down so that it can be compared with the 1.23-V internal

reference. With R2between 1k and 5k, R1is:

R1= R2(VOUT/VREF −1)

where

• VREF = 1.23V (2)

For best temperature coefficient and stability with time, use 1% metal film resistors.

8.2.4.3 Short Circuit Condition

Due to the inherent nature of boost regulators, when the output is shorted (Figure 50), current flows directly from

the input, through the inductor and the diode, to the output, bypassing the switch. The current limit of the switch

does not limit the output current for the entire circuit. To protect the load and prevent damage to the switch, the

current must be externally limited, either by the input supply or at the output with an external current limit circuit.

The external limit should be set to the maximum switch current of the device, which is 3A.

In a flyback regulator application (Figure 43), using the standard transformers, the LM2585 will survive a short

circuit to the main output. When the output voltage drops to 80% of its nominal value, the frequency drops to 25

kHz. With a lower frequency, off times are larger. With the longer off times, the transformer can release all of its

stored energy before the switch turns back on. Hence, the switch turns on initially with zero current at its

collector. In this condition, the switch current limit will limit the peak current, saving the device.

Figure 43. Flyback Regulator

8.2.4.4 Flyback Regulator Input Capacitors

A flyback regulator draws discontinuous pulses of current from the input supply. Therefore, there are two input

capacitors needed in a flyback regulator; one for energy storage and one for filtering (Figure 43). Both are

required due to the inherent operation of a flyback regulator. To keep a stable or constant voltage supply to the

LM2585, a storage capacitor (≥100 μF) is required. If the input source is a rectified DC supply and/or the

application has a wide temperature range, the required rms current rating of the capacitor might be very large.

This means a larger value of capacitance or a higher voltage rating will be needed of the input capacitor. The

storage capacitor will also attenuate noise which may interfere with other circuits connected to the same input

supply voltage.

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

In addition, a small bypass capacitor is required due to the noise generated by the input current pulses. To

eliminate the noise, insert a 1.0 μF ceramic capacitor between VIN and ground as close as possible to the device.

8.2.4.5 Switch Voltage Limits

In a flyback regulator, the maximum steady-state voltage appearing at the switch, when it is off, is set by the

transformer turns ratio, N, the output voltage, VOUT, and the maximum input voltage, VIN (maximum):

VSW(OFF) = VIN (Max) + (VOUT +VF)/N

where

• VFis the forward biased voltage of the output diode and is 0.5 V for Schottky diodes and 0.8 V for ultra-fast

recovery diodes (typically). (3)

In certain circuits, there exists a voltage spike, VLL, superimposed on top of the steady-state voltage (Figure 13,

waveform A). Usually, this voltage spike is caused by the transformer leakage inductance and/or the output

rectifier recovery time. To “clamp” the voltage at the switch from exceeding its maximum value, a transient

suppressor in series with a diode is inserted across the transformer primary (as shown in the circuit on the front

page and other flyback regulator circuits throughout the datasheet). The schematic in Figure 43 shows another

method of clamping the switch voltage. A single voltage transient suppressor (the SA51A) is inserted at the

switch pin. This method clamps the total voltage across the switch, not just the voltage across the primary.

If poor circuit layout techniques are used (see Layout Guidelines), negative voltage transients may appear on the

Switch pin (pin 4). Applying a negative voltage (with respect to the IC's ground) to any monolithic IC pin causes

erratic and unpredictable operation of that IC. This holds true for the LM2585 IC as well. When used in a flyback

regulator, the voltage at the Switch pin (pin 4) can go negative when the switch turns on. The “ringing” voltage at

the switch pin is caused by the output diode capacitance and the transformer leakage inductance forming a

resonant circuit at the secondary(ies). The resonant circuit generates the “ringing” voltage, which gets reflected

back through the transformer to the switch pin. There are two common methods to avoid this problem. One is to

add an RC snubber around the output rectifier(s), as in Figure 43. The values of the resistor and the capacitor

must be chosen so that the voltage at the Switch pin does not drop below −0.4 V. The resistor may range in

value between 10 Ωand 1 kΩ, and the capacitor will vary from 0.001 μF to 0.1 μF. Adding a snubber will

(slightly) reduce the efficiency of the overall circuit.

The other method to reduce or eliminate the “ringing” is to insert a Schottky diode clamp between pins 4 and 3

(ground), also shown in Figure 43. This prevents the voltage at pin 4 from dropping below −0.4 V. The reverse

voltage rating of the diode must be greater than the switch off voltage.

8.2.4.6 Output Voltage Limitations

The maximum output voltage of a boost regulator is the maximum switch voltage minus a diode drop. In a

flyback regulator, the maximum output voltage is determined by the turns ratio, N, and the duty cycle, D, by the

equation:

VOUT ≈N × VIN × D/(1 −D) (4)

The duty cycle of a flyback regulator is determined by the following equation:

(5)

Theoretically, the maximum output voltage can be as large as desired—just keep increasing the turns ratio of the

transformer. However, there exists some physical limitations that prevent the turns ratio, and thus the output

voltage, from increasing to infinity. The physical limitations are capacitances and inductances in the LM2585

switch, the output diode(s), and the transformer—such as reverse recovery time of the output diode (mentioned

above).

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Figure 44. Input Line Filter

8.2.4.7 Noisy Input Line Condition

A small, low-pass RC filter should be used at the input pin of the LM2585 if the input voltage has an unusual

large amount of transient noise, such as with an input switch that bounces. The circuit in Figure 44 demonstrates

the layout of the filter, with the capacitor placed from the input pin to ground and the resistor placed between the

input supply and the input pin. Note that the values of RIN and CIN shown in the schematic are good enough for

most applications, but some readjusting might be required for a particular application. If efficiency is a major

concern, replace the resistor with a small inductor (say 10 μH and rated at 100 mA).

8.2.4.8 Stability

All current-mode controlled regulators can suffer from an instability, known as subharmonic oscillation, if they

operate with a duty cycle above 50%. To eliminate subharmonic oscillations, a minimum value of inductance is

required to ensure stability for all boost and flyback regulators. The minimum inductance is given by:

where

• VSAT is the switch saturation voltage and can be found in the Characteristic Curves. (6)

Figure 45. Circuit Board Layout

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

8.2.5 Application Curve

Figure 46. Supply Current vs Switch Current

8.3 Additional Application Examples

8.3.1 Test Circuits

CIN1—100 μF, 25V Aluminum Electrolytic

CIN2—0.1 μF Ceramic

T—22 μH, 1:1 Schott #67141450

D—1N5820

COUT—680 μF, 16V Aluminum Electrolytic

CC—0.47 μF Ceramic

RC—2k

Figure 47. Lm2585-3.3 And Lm2585-5.0

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Additional Application Examples (continued)

CIN1—100 μF, 25V Aluminum Electrolytic

CIN2—0.1 μF Ceramic

L—15 μH, Renco #RL-5472-5

D—1N5820

COUT—680 μF, 16V Aluminum Electrolytic

CC—0.47 μF Ceramic

RC—2k

For 12V Devices: R1= Short (0Ω) and R2= Open

For ADJ Devices: R1= 48.75k, ±0.1% and R2 = 5.62k, ±1%

Figure 48. Lm2585-12 And Lm2585-Adj

Figure 49. Flyback Regulator

Figure 50. Boost Regulator

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

9 Layout

9.1 Layout Guidelines

As in any switching regulator, layout is very important. Rapidly switching currents associated with wiring

inductance generate voltage transients which can cause problems. For minimal inductance and ground loops,

keep the length of the leads and traces as short as possible. Use single point grounding or ground plane

construction for best results. Separate the signal grounds from the power grounds (as indicated in Figure 45).

When using the Adjustable version, physically locate the programming resistors as near the regulator IC as

possible, to keep the sensitive feedback wiring short.

9.2 Heat Sink/Thermal Considerations

In many cases, no heat sink is required to keep the LM2585 junction temperature within the allowed operating

range. For each application, to determine whether or not a heat sink will be required, the following must be

identified:

1) Maximum ambient temperature (in the application).

2) Maximum regulator power dissipation (in the application).

3) Maximum allowed junction temperature (125°C for the LM2585). For a safe, conservative design, a

temperature approximately 15°C cooler than the maximum junction temperature should be selected (110°C).

4) LM2585 package thermal resistances θJA and θJC (given in Thermal Information).

Total power dissipated (PD) by the LM2585 can be estimated as follows:

where

• VIN is the minimum input voltage

• VOUT is the output voltage

• N is the transformer turns ratio

• D is the duty cycle

• ILOAD is the maximum load current (and ∑ILOAD is the sum of the maximum load currents for multiple-output

flyback regulators) (7)

The duty cycle is given by:

where

• VFis the forward biased voltage of the diode and is typically 0.5V for Schottky diodes and 0.8V for fast

recovery diodes

• VSAT is the switch saturation voltage and can be found in the Characteristic Curves (8)

When no heat sink is used, the junction temperature rise is:

ΔTJ= PD×θJA. (9)

Adding the junction temperature rise to the maximum ambient temperature gives the actual operating junction

temperature:

TJ=ΔTJ+ TA. (10)

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

Heat Sink/Thermal Considerations (continued)

If the operating junction temperature exceeds the maximum junction temperatue in item 3 above, then a heat

sink is required. When using a heat sink, the junction temperature rise can be determined by the following:

ΔTJ= PD× (θJC +θInterface +θHeat Sink) (11)

Again, the operating junction temperature will be:

TJ=ΔTJ+ TA(12)

As before, if the maximum junction temperature is exceeded, a larger heat sink is required (one that has a lower

thermal resistance).

Included in the Switchers Made Simple design software is a more precise (non-linear) thermal model that can

be used to determine junction temperature with different input-output parameters or different component values.

It can also calculate the heat sink thermal resistance required to maintain the regulator junction temperature

below the maximum operating temperature.

LM2585

www.ti.com

SNVS120G –APRIL 2000–REVISED MAY 2019

Product Folder Links: LM2585

10 Device and Documentation Support

10.1 Device Support

10.1.1 Third-Party Products Disclaimer

TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT

CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES

OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER

ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.

10.1.2 Development Support

10.1.2.1 Custom Design With WEBENCH® Tools

Click here to create a custom design using the LM2585 device with the WEBENCH® Power Designer.

1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.

2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.

3. Compare the generated design with other possible solutions from Texas Instruments.

The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time

pricing and component availability.

In most cases, these actions are available:

• Run electrical simulations to see important waveforms and circuit performance

• Run thermal simulations to understand board thermal performance

• Export customized schematic and layout into popular CAD formats

• Print PDF reports for the design, and share the design with colleagues

Get more information about WEBENCH tools at www.ti.com/WEBENCH.

10.2 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.

10.3 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.

10.4 Trademarks

E2E is a trademark of Texas Instruments.

WEBENCH is a registered trademark of Texas Instruments.

All other trademarks are the property of their respective owners.

10.5 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.

LM2585

SNVS120G –APRIL 2000–REVISED MAY 2019

www.ti.com

Product Folder Links: LM2585

10.6 Glossary

SLYZ022 —TI Glossary.

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

11 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 9-Jun-2020

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

LM2585S-12/NOPB ACTIVE DDPAK/

TO-263 KTT 5 45 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-12 P+

LM2585S-3.3/NOPB ACTIVE DDPAK/

TO-263 KTT 5 45 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-3.3 P+

LM2585S-5.0/NOPB ACTIVE DDPAK/

TO-263 KTT 5 45 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-5.0 P+

LM2585S-ADJ NRND DDPAK/

TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2585S

-ADJ P+

LM2585S-ADJ/NOPB ACTIVE DDPAK/

TO-263 KTT 5 45 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-ADJ P+

LM2585SX-12/NOPB ACTIVE DDPAK/

TO-263 KTT 5 500 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-12 P+

LM2585SX-5.0 NRND DDPAK/

TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2585S

-5.0 P+

LM2585SX-5.0/NOPB ACTIVE DDPAK/

TO-263 KTT 5 500 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-5.0 P+

LM2585SX-ADJ/NOPB ACTIVE DDPAK/

TO-263 KTT 5 500 Green (RoHS

& no Sb/Br) SN Level-3-245C-168 HR -40 to 125 LM2585S

-ADJ P+

LM2585T-12/NOPB ACTIVE TO-220 NDH 5 45 Green (RoHS

& no Sb/Br) SN Level-1-NA-UNLIM -40 to 125 LM2585T

-12 P+

LM2585T-3.3/NOPB ACTIVE TO-220 NDH 5 45 Green (RoHS

& no Sb/Br) SN Level-1-NA-UNLIM -40 to 125 LM2585T

-3.3 P+

LM2585T-5.0/NOPB ACTIVE TO-220 NDH 5 45 Green (RoHS

& no Sb/Br) SN Level-1-NA-UNLIM -40 to 125 LM2585T

-5.0 P+

LM2585T-ADJ NRND TO-220 NDH 5 45 TBD Call TI Call TI -40 to 125 LM2585T

-ADJ P+

LM2585T-ADJ/NOPB ACTIVE TO-220 NDH 5 45 Green (RoHS

& no Sb/Br) SN Level-1-NA-UNLIM -40 to 125 LM2585T

-ADJ P+

(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.

PACKAGE OPTION ADDENDUM

www.ti.com 9-Jun-2020

Addendum-Page 2

(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/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

LM2585SX-12/NOPB DDPAK/

TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2

LM2585SX-5.0 DDPAK/

TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2

LM2585SX-5.0/NOPB DDPAK/

TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2

LM2585SX-ADJ/NOPB DDPAK/

TO-263 KTT 5 500 330.0 24.4 10.75 14.85 5.0 16.0 24.0 Q2

PACKAGE MATERIALS INFORMATION

www.ti.com 29-Sep-2019

Pack Materials-Page 1

*All dimensions are nominal

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

LM2585SX-12/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0

LM2585SX-5.0 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0

LM2585SX-5.0/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0

LM2585SX-ADJ/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0

PACKAGE MATERIALS INFORMATION

www.ti.com 29-Sep-2019

Pack Materials-Page 2

MECHANICAL DATA

NDH0005D

www.ti.com

MECHANICAL DATA

KTT0005B

www.ti.com

BOTTOM SIDE OF PACKAGE

TS5B (Rev D)

IMPORTANT NOTICE AND DISCLAIMER

TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE

DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”

AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY

IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD

PARTY INTELLECTUAL PROPERTY RIGHTS.

These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate

TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable

standards, and any other safety, security, or other requirements. These resources are subject to change without notice. TI grants you

permission to use these resources only for development of an application that uses the TI products described in the resource. Other

reproduction and display of these resources is prohibited. No license is granted to any other TI intellectual property right or to any third

party intellectual property right. TI disclaims responsibility for, and you will fully indemnify TI and its representatives against, any claims,

damages, costs, losses, and liabilities arising out of your use of these resources.

TI’s products are provided subject to TI’s Terms of Sale (www.ti.com/legal/termsofsale.html) or other applicable terms available either on

ti.com or provided in conjunction with such TI products. TI’s provision of these resources does not expand or otherwise alter TI’s applicable

warranties or warranty disclaimers for TI products.

Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265