LM2585 - SIMPLE SWITCHER 3-Amp Flyback Regulator

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	LM2585 - SIMPLE SWITCHER 3-Amp Flyback Regulator

Datasheet	Packaging	Samples & Pricing	Reliability	Design Tools	Application Notes	Knowledge Base

Features

•	Requires few external components
•	Family of standard inductors and transformers
•	NPN output switches 3.0A, can stand off 65V
•	Wide input voltage range: 4V to 40V
•	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, under voltage lockout, and thermal shutdown
•	System Output Voltage Tolerance of ±4% max over line and load conditions

General Description

The LM2585 series of regulators are monolithic integrated circuits specifically designed for flyback, step-up (boost), and forward converter applications. More...

Typical Application

*click for larger image

Parametric Table expand

Parametric Table collapse

Output Range 1.23V min, 5V, 12V, 3.3V

Switch Current 3 Amp

Input Min Voltage 4 Volt

Input Max Voltage 40 Volt

Feedback Voltage 3.3, 1.23, 12, 5 Volt

Frequency Max 100000 Hz

Output Range 1.23V min, 5V, 12V, 3.3V

Switch Current 3 Amp

Input Min Voltage 4 Volt

Input Max Voltage 40 Volt

Feedback Voltage 3.3, 1.23, 12, 5 Volt

Frequency Max 100000 Hz

Sync Pin No

Adj Switch Frequency No

Frequency Min 100000 Hz

On/Off Pin No

Error Flag No

SoftStart Yes

Special Features SIMPLE SWITCHER regulator

Topology Boost, Flyback

Step-Up Yes

Inverting No

Flyback Yes

RegType Switching Regulator

Adjustable Output Yes, No

Efficiency (peak) 93, 80, 76 %

Temperature Min -40 deg C

Temperature Max 125 deg C

Regulator Family SIMPLE SWITCHER

View Using Catalog

Typical Performance

*click for larger image

WEBENCH Live Simulation!

LM2585 WEBENCH® Custom Design/Analyze/Build It/Test It
4.00 <=	V in Lower V	<=	V in Upper V	<= 40.00
V out	1.23 <=		V	<= 300.00
I out			A	<= 3.00
Ambient Temperature			°C	<= 100
What are WEBENCH® tools?

Also Recommended

LM2586	LM2585 W/ Synchronizable, Adjustable Freq. And Soft Start
LM2587	5A Version Of LM2585
LM2700	Higher Frequency (600Khz, 1.25Mhz), Smaller Package, 3.6A Switch
LM5000	Higher Frequency (300Khz To 1.25Mhz), 2A 80V Integrated Switch In Smaller Package
LM2623	Miniature 2.2A Switch (A Grade), Low Cost Versatile Converter

Additional Resources

Online Seminars

SIMPLE SWITCHER® Topologies and their Morphology

Design Tools (see below)

Application Notes (see below)

Block Diagram

click for larger image

Datasheet

RoHS Compliance Information	Size in Kbytes	Date
LM2585 SIMPLE SWITCHER 3A Flyback Regulator	991 Kbytes	8-Mar-07	View Online	Download	Receive via Email
LM2585 SIMPLE SWITCHER 3A Flyback Regulator (Japanese)	331 Kbytes

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Package Availability, Models, Samples & Pricing

Part Number

Package

Factory Lead Time

Models

Samples &
Electronic
Orders

Budgetary Pricing

Std
Pack
Size

Package
Marking
Format

Type

Pins

Spec.

MSL
Rating

Peak
Reflow

RoHS
Report

CAD
Symbols

Qty

Qty

$US each

LM2585T-12

5

NOPB

1

NA

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585T
-12 P+

6 weeks

1000

LM2585T-3.3

5

NOPB

1

NA

Full production

N/A

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585T
-3.3 P+

6 weeks

N/A

LM2585T-5.0

5

STD

NOPB

1

1

NA

NA

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585T
-5.0 P+

6 weeks

1000

LM2585T-ADJ

5

STD

NOPB

1

1

NA

NA

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585T
-ADJ P+

6 weeks

500

LM2585S-12

5

STD

NOPB

3

3

235

245

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585S
-12 P+

6 weeks

500

LM2585S-3.3

5

NOPB

3

245

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585S
-3.3 P+

6 weeks

100

LM2585S-5.0

5

NOPB

3

245

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585S
-5.0 P+

6 weeks

500

LM2585S-ADJ

5

STD

NOPB

3

3

235

245

Full production

N/A

Samples

1K+

$3.17

rail
of
45

NSUZXYTT
LM2585S
-ADJ P+

6 weeks

1000

LM2585SX-12

5

STD

NOPB

3

3

235

245

Full production

N/A

1K+

$3.17

reel
of
500

NSUZXYTT
LM2585S
-12 P+

6 weeks

2500

LM2585SX-3.3

5

NOPB

3

245

Full production

N/A

1K+

$3.17

reel
of
500

NSUZXYTT
LM2585S
-3.3 P+

6 weeks

N/A

LM2585SX-5.0

5

STD

NOPB

3

3

235

245

Full production

N/A

1K+

$3.17

reel
of
500

NSUZXYTT
LM2585S
-5.0 P+

8 weeks

2500

LM2585SX-ADJ

5

STD

NOPB

3

3

235

245

Full production

N/A

1K+

$3.17

reel
of
500

NSUZXYTT
LM2585S
-ADJ P+

6 weeks

2000

General 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: 3.3V, 5.0V, 12V, 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 3.0A NPN device that can stand-off 65V. 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 guaranteed for the power supply system.

Reliability Metrics

Part Number	Process	Early Failure Rate - Rejects	Sample Size (EFR)	PPM *	Rel. Rejects	Device Hours	Long Term Failure Rates (FITS)	MTTF
LM2585S-12	SLM	0	33020	0	0	1687500	3	478832732
LM2585S-3.3	SLM	0	33020	0	0	1687500	3	478832732
LM2585S-5.0	SLM	0	33020	0	0	1687500	3	478832732
LM2585S-ADJ	SLM	0	33020	0	0	1687500	3	478832732
LM2585SX-12	SLM	0	33020	0	0	1687500	3	478832732
LM2585SX-3.3	SLM	0	33020	0	0	1687500	3	478832732
LM2585SX-5.0	SLM	0	33020	0	0	1687500	3	478832732
LM2585SX-ADJ	SLM	0	33020	0	0	1687500	3	478832732
LM2585T-12	SLM	0	33020	0	0	1687500	3	478832732
LM2585T-3.3	SLM	0	33020	0	0	1687500	3	478832732
LM2585T-5.0	SLM	0	33020	0	0	1687500	3	478832732
LM2585T-ADJ	SLM	0	33020	0	0	1687500	3	478832732

For more information on Reliability Metrics, please click here.

Design Tools

Title	Size in Kbytes	Date
SimpleSwitcher® DC-DC Converters Design Software	12 Kbytes	11-Jan-2008	View

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Application Notes

Title	Size in Kbytes	Date
AN-1149: Application Note 1149 Layout Guidelines for Switching Power Supplies	113 Kbytes	26-Sep-02	View Online	Download	Receive via Email
AN-1149 (Japanese): Application Note 1149 Layout Guidelines for Switching Power Supplies	90 Kbytes
AN-1082: Application Note 1082 Adjust or Synchronize LM2586/88 Switching Frequency	50 Kbytes	18-Sep-02	View Online	Download	Receive via Email
AN-1082 (Japanese): Application Note 1082 Adjust or Synchronize LM2586/88 Switching Frequency	85 Kbytes
AN-1061: Application Note 1061 Power Conversion in Line-Powered Equipment	188 Kbytes	1-Oct-02	View Online	Download	Receive via Email
AN-1061 (Japanese): Application Note 1061 Power Conversion in Line-Powered Equipment	215 Kbytes

If you have trouble printing or viewing PDF file(s), see Printing Problems.

[Information as of 15-May-2008]

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