LM2676 - SIMPLE SWITCHER High Efficiency 3A Step-Down Voltage Regulator

LM2676	SIMPLE SWITCHER High Efficiency 3A Step-Down Voltage Regulator

Overview

Diagrams

Parametrics

Documents

Order

Packaging

Tools

Reliability

Obsolete Versions

Features

Efficiency up to 94%

Simple and easy to design with (using off-the-shelf external components)

150 mΩ DMOS output switch

3.3V, 5V and 12V fixed output and adjustable (1.2V to 37V ) versions

50μA standby current when switched OFF

±2%maximum output tolerance over full line and load conditions

Wide input voltage range: 8V to 40V

260 KHz fixed frequency internal oscillator

−40 to +125°C operating junction temperature range

Description
The LM2676 series of regulators are monolithic integrated circuits which provide all of the active functions for a step-down (buck) switching regulator capable of driving up to 3A loads with excellent line and load regulation characteristics. High efficiency (>90%) is obtained through the use of a low ON-resistance DMOS power switch. The series consists of fixed output voltages of 3.3V, 5V and 12V and an adjustable output version.

The SIMPLE SWITCHER concept provides for a complete design using a minimum number of external components. A high fixed frequency oscillator (260KHz) allows the use of physically smaller sized components. A family of standard inductors for use with the LM2676 are available from several manufacturers to greatly simplify the design process.

The LM2676 series also has built in thermal shutdown, current limiting and an ON/OFF control input that can power down the regulator to a low 50μA quiescent current standby condition. The output voltage is guaranteed to a ±2% tolerance. The clock frequency is controlled to within a ±11% tolerance.

Applications
Simple to design, high efficiency (>90%) step-down switching regulators

Efficient system pre-regulator for linear voltage regulators

Battery chargers

See Layout Guidelines

WEBENCH® LM2676

Min Max Range

VIN – V    8.00 – 40.00V

VOUT V    1.21 – 40.00V

IOUT A    ≤ 3.00A

Ambient Temp °C    ≤ 100°C

Footprint BOM Cost Efficiency

What are WEBENCH® tools?

Also Recommended

LM22676▲ Wider Input Voltage Range (6 To 42V), Fixed 500kHz

LM25576▲ Fast-Transient Response And Higher Switching Frequency (Up To 1MHz)

LM5576▲ 75V Vin 3A Regulator

Typical Application click for larger image

Block Diagram click for larger image

Typical Performance *click for larger image

Parameters / Values	LM2676	LM22676	LM25576	LM5576
Output Current	3000 mA	3000 mA	3000 mA	3000 mA
Input Min Voltage	15, 8 Volt	4.5 Volt	6 Volt	6 Volt
Input Max Voltage	40 Volt	42 Volt	42 Volt	75 Volt
Output Min	3.3, 1.23, 12, 5 Volt	1.285 Volt	1.23 Volt	1.23 Volt
Output Max	3.3, 12, 37, 5 Volt		40 Volt	70 Volt
Frequency Min	260 kHz		50 kHz	50 kHz
Frequency Max	260 kHz		1000 kHz	500 kHz
Efficiency (peak)	94, 88, 86 %	92 %	91 %	88 %
On/Off Pin	Yes	Yes	Yes	Yes
PowerGood / Error Flag	No	No	No	No
SoftStart	No	No	Yes	Yes
Sync Pin	No	No	Yes	Yes
Flyback	No	No	No	No
RegType	Switching Regulator	Switching Regulator	Switching Regulator	Switching Regulator
Temperature Min	-40 deg C	-40 deg C	-40 deg C	-40 deg C
Temperature Max	125 deg C	125 deg C	125 deg C	125 deg C
Adjustable Output	Yes, No	Yes	Yes	Yes
Adj Switch Frequency	No	No	Yes	Yes
PWM Mode	Voltage with Vin Feedforward	Voltage Mode Control	Current	Current
Topology	Buck	Buck	Buck	Buck
Special Features	Internal Type 3 compensation, 2% output voltage accuracy, SIMPLE SWITCHER regulator	500 kHz Switching Frequency	1.5% feedback voltage accuracy, emulated current mode	1.5% feedback voltage accuracy, emulated current mode
Step-Down	Yes	Yes	Yes	Yes
Multiple Output Capability	No	No	No	No
Output Power	Undefined Watt		Undefined Watt	Undefined Watt
Output Voltage	3.3, 12, Undefined, 5 Volt		Undefined Volt	Undefined Volt
Output Range	12V, 1.23V to 37V, 3.3V, 5V		1.23V to 37V	1.23V to 70V
Switching Frequency	260 kHz	500 kHz	1000 kHz	500 kHz
Regulator Family	SIMPLE SWITCHER	SIMPLE SWITCHER	SIMPLE SWITCHER	SIMPLE SWITCHER
Synchronous Rectification	No	No	No	No

Datasheets
Title Size Date Other
Language

LM2676 SIMPLE SWITCHER High Efficiency 3A Step-Down Voltage Regulator 671
Kbytes 29-Feb-08 日本語

Application Notes
Title Size Date Other
Language

AN-1135: Application Note 1135 LM267X 3A, 5A Evaluation Boards 2433
Kbytes 4-Mar-11

Other Technical Documents
Title Type Date

How to supply, load, and test power-management circuits Part 1 External Article 2008-04-09

Part Number(s)
(NSID)

Top View

Availability

Current Reported Stock

Budgetary Pricing

Pack
Size

LM2676S-12/NOPB

LM2676S-12

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	213
AVNET-EM	Worldwide	1250
BRITESTONE	South Korea	4
DIGI-KEY	Worldwide	1272
FARNELL	Europe and Asia	760
MOUSER	Worldwide	74
NEWARK	Americas	562
RS COMPONENTS	Worldwide	50
TAYLOR	Americas	440

$1.92 each at 1K+ pcs

rail
of
45

LM2676S-3.3/NOPB

LM2676S-3.3

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	551
AVNET-EM	Worldwide	2549
BRITESTONE	South Korea	133
DIGI-KEY	Worldwide	667
MOUSER	Worldwide	169
NEWARK	Americas	5
RS COMPONENTS	Worldwide	119
TAYLOR	Americas	2775

$1.92 each at 1K+ pcs

rail
of
45

LM2676S-5.0/NOPB

LM2676S-5.0

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	715
AVNET-EM	Worldwide	3640
BRITESTONE	South Korea	104
CEAC	Asia Pacific	630
DIGI-KEY	Worldwide	1882
MOUSER	Worldwide	230
NEWARK	Americas	1313
RS COMPONENTS	Worldwide	222
TAYLOR	Americas	6849

$1.92 each at 1K+ pcs

rail
of
45

LM2676S-ADJ/NOPB

LM2676S-ADJ

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	1195
AVNET-EM	Worldwide	72
BRITESTONE	South Korea	8
DIGI-KEY	Worldwide	11298
FARNELL	Europe and Asia	4636
MOUSER	Worldwide	395
NEWARK	Americas	6923
RS COMPONENTS	Worldwide	100
RSL MICRO	Asia Pacific	6300
TAYLOR	Americas	4377
TECHMOSA	Asia Pacific	765

$1.92 each at 1K+ pcs

rail
of
45

LM2676SD-12/NOPB

LM2676SD-12

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	250
AVNET-EM	Worldwide	250
DIGI-KEY	Worldwide	759
MOUSER	Worldwide	150
TAYLOR	Americas	250

$1.92 each at 1K+ pcs

reel
of
250

LM2676SD-3.3/NOPB

LM2676SD-3.3

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	392
AVNET-EM	Worldwide	250
DIGI-KEY	Worldwide	414
MOUSER	Worldwide	50
TAYLOR	Americas	392

$1.92 each at 1K+ pcs

reel
of
250

LM2676SD-5.0/NOPB

LM2676SD-5.0

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	250
AVNET-EM	Worldwide	250
DIGI-KEY	Worldwide	668
MOUSER	Worldwide	150
NEWARK	Americas	254
TAYLOR	Americas	1250

$1.92 each at 1K+ pcs

reel
of
250

LM2676SD-ADJ/NOPB

LM2676SD-ADJ

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	485
AVNET-EM	Worldwide	250
DIGI-KEY	Worldwide	936
MOUSER	Worldwide	150
NEWARK	Americas	178
RS COMPONENTS	Worldwide	250
TAYLOR	Americas	719

$1.92 each at 1K+ pcs

reel
of
250

LM2676SDX-12/NOPB

LM2676SDX-12

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor		Region	Qty
DIGI-KEY		Worldwide	0

$1.92 each at 1K+ pcs

reel
of
2500

LM2676SDX-3.3/NOPB

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor		Region	Qty
DIGI-KEY		Worldwide	0

$1.92 each at 1K+ pcs

reel
of
2500

LM2676SDX-5.0/NOPB

LM2676SDX-5.0

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor		Region	Qty
DIGI-KEY		Worldwide	0

$1.92 each at 1K+ pcs

reel
of
2500

LM2676SDX-ADJ/NOPB

LM2676SDX-ADJ

RoHS Status

LLP

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	5000
DIGI-KEY	Worldwide	0
TAYLOR	Americas	5000

$1.92 each at 1K+ pcs

reel
of
2500

LM2676SX-12/NOPB

LM2676SX-12

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	2450
BRITESTONE	South Korea	2000
DIGI-KEY	Worldwide	0
MOUSER	Worldwide	400
RSL MICRO	Asia Pacific	1500
TAYLOR	Americas	2450

$1.92 each at 1K+ pcs

reel
of
500

LM2676SX-3.3/NOPB

LM2676SX-3.3

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	500
AVNET-EM	Worldwide	1940
DIGI-KEY	Worldwide	0
MOUSER	Worldwide	500
NEWARK	Americas	203
TAYLOR	Americas	1897

$1.92 each at 1K+ pcs

reel
of
500

LM2676SX-5.0/NOPB

LM2676SX-5.0

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	500
AVNET-EM	Worldwide	4000
DIGI-KEY	Worldwide	0
MOUSER	Worldwide	423
NEWARK	Americas	72
RSL MICRO	Asia Pacific	7500
TAYLOR	Americas	14326

$1.92 each at 1K+ pcs

reel
of
500

LM2676SX-ADJ/NOPB

LM2676SX-ADJ

RoHS Status

TO-263

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	1000
AVNET-EM	Worldwide	4000
BRITESTONE	South Korea	2
DIGI-KEY	Worldwide	0
MOUSER	Worldwide	490
TAYLOR	Americas	2221
TECHMOSA	Asia Pacific	500

$1.92 each at 1K+ pcs

reel
of
500

LM2676T-12/NOPB

LM2676T-12

RoHS Status

TO-220

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
AVNET-EM	Worldwide	375
DIGI-KEY	Worldwide	134
FARNELL	Europe and Asia	180
MOUSER	Worldwide	46
NEWARK	Americas	39
RS COMPONENTS	Worldwide	28

$1.92 each at 1K+ pcs

rail
of
45

LM2676T-3.3/NOPB

LM2676T-3.3

RoHS Status

TO-220

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	45
AVNET-EM	Worldwide	170
DIGI-KEY	Worldwide	348
MOUSER	Worldwide	176
RS COMPONENTS	Worldwide	16
TAYLOR	Americas	45

$1.92 each at 1K+ pcs

rail
of
45

LM2676T-5.0/NOPB

LM2676T-5.0

RoHS Status

TO-220

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	275
AVNET-EM	Worldwide	194
BRITESTONE	South Korea	8
DIGI-KEY	Worldwide	1251
MOUSER	Worldwide	178
NEWARK	Americas	11
RS COMPONENTS	Worldwide	49
TAYLOR	Americas	275

$1.92 each at 1K+ pcs

rail
of
45

LM2676T-ADJ/NOPB

LM2676T-ADJ

RoHS Status

TO-220

Full production
Lead Time: 6 weeks

Distributor	Region	Qty
ARROW	Worldwide	3465
AVNET-EM	Worldwide	85
DIGI-KEY	Worldwide	3303
FARNELL	Europe and Asia	1790
MOUSER	Worldwide	165
NEWARK	Americas	29
RS COMPONENTS	Worldwide	60
RSL MICRO	Asia Pacific	4860
TAYLOR	Americas	3465

$1.92 each at 1K+ pcs

rail
of
45

Obsolete Versions

Obsolete Part Alternate Part or Supplier Source Last Time Buy Date

LM2676D-12
NONE
NONE
30 Jan 2004

LM2676LD-3.3
NONE
NONE
30 Jan 2004

LM2676LD-5.0
NONE
NONE
30 Jan 2004

LM2676LD-ADJ
NONE
NONE
30 Jan 2004

LM2676LDX-12
NONE
NONE
30 Jan 2004

LM2676LDX-3.3
NONE
NONE
30 Jan 2004

LM2676LDX-5.0
NONE
NONE
30 Jan 2004

LM2676LDX-ADJ
NONE
NONE
30 Jan 2004

LM2676S-5.0EP
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM2676.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM2676 is located at RoHS Status.

Part Number(s) (NSID)	Weight (milligrams)	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LM2676S-12/NOPB LM2676S-12	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-12
LM2676S-3.3/NOPB LM2676S-3.3	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-3.3
LM2676S-5.0/NOPB LM2676S-5.0	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-5.0
LM2676S-ADJ/NOPB LM2676S-ADJ	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-ADJ
LM2676SD-12/NOPB LM2676SD-12	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003LB
LM2676SD-3.3/NOPB LM2676SD-3.3	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003NB
LM2676SD-5.0/NOPB LM2676SD-5.0	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003PB
LM2676SD-ADJ/NOPB LM2676SD-ADJ	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003RB
LM2676SDX-12/NOPB LM2676SDX-12	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003LB
LM2676SDX-3.3/NOPB	94.439	LLP	14	1	260	Detail	Download	N/A	NS UZXYTT S0003NB
LM2676SDX-5.0/NOPB LM2676SDX-5.0	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003PB
LM2676SDX-ADJ/NOPB LM2676SDX-ADJ	94.439 94.76	LLP	14	1 1	260 260	Detail	Download	N/A	NS UZXYTT S0003RB
LM2676SX-12/NOPB LM2676SX-12	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-12
LM2676SX-3.3/NOPB LM2676SX-3.3	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-3.3
LM2676SX-5.0/NOPB LM2676SX-5.0	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-5.0
LM2676SX-ADJ/NOPB LM2676SX-ADJ	1608.332 1609.822	TO-263	7	3 3	245 235	Detail	Download	N/A	NSUZXYTTE# LM2676 S-ADJ
LM2676T-12/NOPB LM2676T-12	1846.782 1858.793	TO-220	7	1 1	NA NA	Detail	Download	N/A	NSUZXYTTE# LM2676 T-12
LM2676T-3.3/NOPB LM2676T-3.3	1846.782 1858.793	TO-220	7	1 1	NA NA	Detail	Download	N/A	NSUZXYTTE# LM2676 T-3.3
LM2676T-5.0/NOPB LM2676T-5.0	1846.782 1858.793	TO-220	7	1 1	NA NA	Detail	Download	N/A	NSUZXYTTE# LM2676 T-5.0
LM2676T-ADJ/NOPB LM2676T-ADJ	1846.782 1858.793	TO-220	7	1 1	NA NA	Detail	Download	N/A	NSUZXYTTE# LM2676 T-ADJ

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM2676.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM2676 is located at RoHS Status.

Design Tools
Title Size Date

"Article - How to supply, load, and test power-management circuits Part 1"

Article - Supplying and Loading of Power Management Circuits Part 2

Reference Design

RD-143 - Lowest Power 8-bit 3 GSPS Data Acquisition System

CAD Symbols and Models
Download LM2676 CAD Symbols

Models
N/A

Reliability Metrics

Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)

LM2676S-12 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676S-3.3 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676S-5.0 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676S-ADJ LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SD-12 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SD-3.3 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SD-5.0 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SD-ADJ LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SDX-12 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SDX-3.3 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SDX-5.0 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SDX-ADJ LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SX-12 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SX-3.3 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SX-5.0 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676SX-ADJ LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676T-12 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676T-3.3 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676T-5.0 LMDMOS 0 18295 0 0 2650000 2 751944735

LM2676T-ADJ LMDMOS 0 18295 0 0 2650000 2 751944735

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

For more information on Reliability Metrics, please click here.

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM2676.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM2676 is located at RoHS Status.

[Information as of 8-Feb-2012]

For technical questions regarding TI and National Semiconductor products:

TI E2E™ Community (engineer-to-engineer online forums where you can ask questions to your fellow engineers and TI experts, as well as search for similar questions/answers)
TI Product Information Center (TI's email/phone support hotline for your region of the world)

Sign-on to save and manage products in your MyBriefcase, order free samples, create WEBENCH designs in minutes, and set your personal preferences.