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LM2674  Product Folder

SIMPLE SWITCHER Power Converter High Efficiency 500mA Step-Down Voltage Regulator
  

See Also:		   
LM2671 - Has softstart, frequency synchronization pin.
     LM2619 - HIGHER SWITCHING FREQUENCY, SMALLER PACKAGE, SYNCHRONOUS-RECTIFICATION FOR HIGHER EFFICIENCY
     LM2675 - 1A OUTPUT CURRENT
     LM2594HV - 4.5V TO 60V INPUT VOLTAGE RANGE
Generic P/N 2674
General
Description		 Features Datasheet Package
& Models		 Samples
& Pricing		 Reliability
Metrics		 Design
Tools		 Application
Notes

WEBENCH Live Simulation!
LM2674 Webench™ Custom
Design/Analyze/Build It
 
8.0 <=		 V in Lower
V		  
<=		 V in Upper
V		  
<= 40.0
V out 1.2 <= V <= 40.0
I out   A <= 0.50
Ambient Temperature °C <= 100

What is Webench?
  
Parametric Table
Temperature Min (deg C) -40 
Temperature Max (deg C) 125 
Multiple Output Capability No 
On/Off Pin Yes 
Error Flag No 
InputMin Voltage (Volt) 15, 6.50 
InputMax Voltage (Volt) 40 
Output Current (mA) 500 
Output Voltage (Volt) 12, 3.30, 5 
Adjustable Output No, Yes 
Output Range 1.2V-37V 
Switching Frequency (Hz) 260000 
Adj Switch Frequency No 
Sync Pin No 
Efficiency (%) 94, 86, 90 
Flyback No 
Step-Up No 
Step-Down Yes 
RegType Switching Regulator 
-

Datasheet

TitleSize in KbytesDate
View Online
Download
Receive via Email
LM2674 SIMPLE SWITCHER Power Converter High Efficiency 500 mA Step-Down Voltage Regulator 494 Kbytes 10-May-01 View Online Download Receive via Email
LM2674 SIMPLE SWITCHER Power Converter High Efficiency 500 mA Step-Down Voltage Regulator (JAPANESE)
 271 Kbytes   View Online Download Receive via Email

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

Package Availability, Models, Samples & Pricing

Part NumberPackageStatusModelsSamples &
Electronic
Orders		Budgetary PricingStd
Pack
Size		Package
Marking
TypePinsMSL/Lead-Free AvailabilityLead
Time		QtySPICEIBISQty$US each
LM2674LD-12LLP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31reel
of
1000		NS
UZXYTT
S0009B
13-15 weeks50000
LM2674LD-3.3LLP16StatusFull productionN/AN/A24 Hour Samples
Buy Now		1K+$1.31reel
of
1000		NS
UZXYTT
S000AB
13-15 weeks50000
LM2674LD-5.0LLP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31reel
of
1000		NS
UZXYTT
S000BB
13-15 weeks50000
LM2674LD-ADJLLP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31reel
of
1000		NS
UZXYTT
S000CB
13-15 weeks50000
LM2674LDX-12LLP16StatusFull productionN/AN/A 1K+$1.31reel
of
4500		NS
UZXYTT
S0009B
13-15 weeks50000
LM2674LDX-3.3LLP16StatusFull productionN/AN/A 1K+$1.31reel
of
4500		NS
UZXYTT
S000AB
13-15 weeks50000
LM2674LDX-5.0LLP16StatusFull productionN/AN/A 1K+$1.31reel
of
4500		NS
UZXYTT
S000BB
13-15 weeks50000
LM2674LDX-ADJLLP16StatusFull productionN/AN/A 1K+$1.31reel
of
4500		NS
UZXYTT
S000CB
13-15 weeks50000
LM2674M-12SOIC NARROW8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
95		NSXYTT
2674
M-12
12-14 weeks20000
LM2674M-3.3SOIC NARROW8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
95		NSXYTT
2674
M3.3
5-7 weeks20000
LM2674M-5.0SOIC NARROW8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
95		NSXYTT
2674
M5.0
12-14 weeks20000
LM2674M-ADJSOIC NARROW8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
95		NSXYTT
2674
MADJ
12-14 weeks20000
LM2674MX-12SOIC NARROW8StatusFull productionN/AN/A 1K+$1.31reel
of
2500		NSXYTT
2674
M-12
12-14 weeks20000
LM2674MX-3.3SOIC NARROW8StatusFull productionN/AN/A 1K+$1.31reel
of
2500		NSXYTT
2674
M3.3
5-7 weeks20000
LM2674MX-5.0SOIC NARROW8StatusFull productionN/AN/A 1K+$1.31reel
of
2500		NSXYTT
2674
M5.0
12-14 weeks20000
LM2674MX-ADJSOIC NARROW8StatusFull productionN/AN/A 1K+$1.31reel
of
2500		NSXYTT
2674
MADJ
12-14 weeks20000
LM2674N-12MDIP8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
40		NSUZXYTT
LM2674
N-12
12-14 weeks20000
LM2674N-3.3MDIP8StatusFull productionN/AN/A24 Hour Samples
Buy Now		1K+$1.31rail
of
40		NSUZXYTT
LM2674
N-3.3
5-7 weeks20000
LM2674N-5.0MDIP8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
40		NSUZXYTT
LM2674
N-5.0
12-14 weeks20000
LM2674N-ADJMDIP8StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$1.31rail
of
40		NSUZXYTT
LM2674
N-ADJ
12-14 weeks20000
LM2674-12 MDCUnpackaged DieFull productionN/AN/A   gel pak
of
N/A		-
N/A0
LM2674-3.3 MDCUnpackaged DieFull productionN/AN/A   gel pak
of
N/A		-
N/A0
LM2674-5.0 MDCUnpackaged DieFull productionN/AN/A   gel pak
of
N/A		-
N/A0
LM2674-ADJ MDCUnpackaged DieFull productionN/AN/ASamples  gel pak
of
N/A		-
N/A0
LM2674-12 MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0
LM2674-3.3 MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0
LM2674-5.0 MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0
LM2674-ADJ MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0

General Description

The LM2674 series of regulators are monolithic integrated circuits built with a LMDMOS process. These regulators provide all the active functions for a step-down (buck) switching regulator, capable of driving a 500 mA load current with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5.0V, 12V, and an adjustable output version.

Requiring a minimum number of external components, these regulators are simple to use and include patented internal frequency compensation (Patent Nos. 5,382,918 and 5,514,947) and a fixed frequency oscillator.

The LM2674 series operates at a switching frequency of 260 kHz, thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Because of its very high efficiency (>90%), the copper traces on the printed circuit board are the only heat sinking needed.

A family of standard inductors for use with the LM2674 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies using these advanced ICs. Also included in the datasheet are selector guides for diodes and capacitors designed to work in switch-mode power supplies.

Other features include a guaranteed ±1.5% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring typically 50 µA stand-by current. The output switch includes current limiting, as well as thermal shutdown for full protection under fault conditions.

To simplify the LM2674 buck regulator design procedure, there exists computer design software, LM267X Made Simple (version 6.0).

Features

  • Efficiency up to 96%
  • Available in SO-8, 8-pin DIP and LLP packages
  • Computer Design Software LM267X Made Simple (version 6.0)
  • Simple and easy to design with
  • Requires only 5 external components
  • Uses readily available standard inductors
  • 3.3V, 5.0V, 12V, and adjustable output versions
  • Adjustable version output voltage range: 1.21V to 37V
  • ±1.5% max output voltage tolerance over line and load conditions
  • Guaranteed 500mA output load current
  • 0.25 DMOS Output Switch
  • Wide input voltage range: 8V to 40V
  • 260 kHz fixed frequency internal oscillator
  • TTL shutdown capability, low power standby mode
  • Thermal shutdown and current limit protection

Applications

  • Simple High Efficiency (>90%) Step-Down (Buck) Regulator
  • Efficient Pre-Regulator for Linear Regulators
  • Positive-to-Negative Converter

Reliability Metrics

Part Number Process Early Failure Rate - Rejects Sample Size (EFR) PPM * Rel. Rejects Device Hours Long Term Failure Rates (FITS) MTTF
LM2674-12 MDCLMDMOS09700004800006814846805
LM2674-12 MWCLMDMOS09700004800006814846805
LM2674-3.3 MDCLMDMOS09700004800006814846805
LM2674-3.3 MWCLMDMOS09700004800006814846805
LM2674-5.0 MDCLMDMOS09700004800006814846805
LM2674-5.0 MWCLMDMOS09700004800006814846805
LM2674-ADJ MDCLMDMOS09700004800006814846805
LM2674-ADJ MWCLMDMOS09700004800006814846805
LM2674LD-12LMDMOS09700004800006814846805
LM2674LD-3.3LMDMOS09700004800006814846805
LM2674LD-5.0LMDMOS09700004800006814846805
LM2674LD-ADJLMDMOS09700004800006814846805
LM2674LDX-12LMDMOS09700004800006814846805
LM2674LDX-3.3LMDMOS09700004800006814846805
LM2674LDX-5.0LMDMOS09700004800006814846805
LM2674LDX-ADJLMDMOS09700004800006814846805
LM2674M-12LMDMOS09700004800006814846805
LM2674M-3.3LMDMOS09700004800006814846805
LM2674M-5.0LMDMOS09700004800006814846805
LM2674M-ADJLMDMOS09700004800006814846805
LM2674MX-12LMDMOS09700004800006814846805
LM2674MX-3.3LMDMOS09700004800006814846805
LM2674MX-5.0LMDMOS09700004800006814846805
LM2674MX-ADJLMDMOS09700004800006814846805
LM2674N-12LMDMOS09700004800006814846805
LM2674N-3.3LMDMOS09700004800006814846805
LM2674N-5.0LMDMOS09700004800006814846805
LM2674N-ADJLMDMOS09700004800006814846805

For more information on Reliablitity Metrics, please click here.


Design Tools

TitleSize in KbytesDate
View Online
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SimpleSwitcher® DC-DC Converters Design Software 9 Kbytes 28-Jul-2003 View    

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Application Notes

TitleSize in KbytesDate
View Online
Download
Receive via Email
AN-1061: Application Note 1061 Power Conversion in Line-Powered Equipment 188 Kbytes 1-Oct-02 View Online Download Receive via Email
AN-1149: Application Note 1149 Layout Guidelines for Switching Power Supplies 113 Kbytes 26-Sep-02 View Online Download Receive via Email
AN-1157: Application Note 1157 Positive to Negative Buck-Boost Converter Using LM267X SIMPLE SWITCHER® Regulators 189 Kbytes 1-Oct-02 View Online Download Receive via Email
AN-1187: Application Note 1187 Leadless Leadframe Package (LLP) 1463 Kbytes 26-Sep-03 View Online Download Receive via Email
Application Note 1187 Leadless Leadframe Package (LLP) (JAPANESE)
 5326 Kbytes   View Online Download Receive via Email
AN-1197: Application Note 1197 Selecting Inductors for Buck Converters 371 Kbytes 1-Oct-02 View Online Download Receive via Email
AN-1229: Application Note 1229 SIMPLE SWITCHER PCB Layout Guidelines 229 Kbytes 1-Oct-02 View Online Download Receive via Email
AN-1246: Application Note 1246 Stresses in Wide Input DC-DC Converters 272 Kbytes 26-Sep-02 View Online Download Receive via Email
AN-556: Application Note 556 Introduction to Power Supplies 159 Kbytes 25-Sep-02 View Online Download Receive via Email

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

[Information as of 15-Jan-2004]

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