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LM2651  Product Folder

1.5A High Efficiency Switching Regulator
  

See Also:		   
LM2653 - More features including PGOOD flag w/ adjustable DELAY
     LM2650 - 3A INTEGRATED SYNCHRONOUS REGULATOR W/ ADJ FREQUENCY AND SYNC PIN
     LM2727 - SYNCHRONOUS CONTROLLER WITH SUB-BANDGAP REFERENCE (OUTPUT VOLTAGES AS LOW AS 0.6V)
Generic P/N 2651
General
Description		 Features Datasheet Package
& Models		 Samples
& Pricing		 Reliability
Metrics		 Application
Notes

WEBENCH Live Simulation!
LM2651 Webench™ Custom
Design/Analyze/Build It
 
4.0 <=		 V in Lower
V		  
<=		 V in Upper
V		  
<= 14.0
V out 1.2 <= V <= 14.0
I out   A <= 1.50
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) 4 
InputMax Voltage (Volt) 14 
Output Current (mA) 1500 
Output Voltage (Volt) 3.30, 1.80, 2.50 
Adjustable Output No, Yes 
Output Range 1.238V min. 
Switching Frequency (Hz) 300000 
Adj Switch Frequency No 
Sync Pin No 
Efficiency (%) 97, 87 
Flyback No 
Inverting No 
Step-Up No 
Step-Down Yes 
RegType Switching Regulator 
-

Datasheet

TitleSize in KbytesDate
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Download
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LM2651 1.5A High Efficiency Synchronous Switching Regulator 224 Kbytes 2-Apr-01 View Online Download Receive via Email
LM2651 1.5A High Efficiency Synchronous Switching Regulator (JAPANESE)
 393 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
LM2651-3.3EVALevaluation boardFull productionN/AN/A 
Buy Now		1+$20.001-
N/A0
LM2651EVALevaluation boardFull productionN/AN/A 
Buy Now		1+$20.001-
N/A0
LM2651MTC-1.8TSSOP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$2.95rail
of
92		NSZXYTT
2651MTC
-1.8
14-16 weeks25000
LM2651MTC-2.5TSSOP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$2.95rail
of
92		NSZXYTT
2651MTC
-2.5
13-15 weeks25000
LM2651MTC-3.3TSSOP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$2.95rail
of
92		NSZXYTT
2651MTC
-3.3
14-16 weeks25000
LM2651MTC-ADJTSSOP16StatusFull productionN/AN/A24 Hour Samples
Buy Now 		1K+$2.95rail
of
92		NSZXYTT
2651MTC
-ADJ
14-16 weeks25000
LM2651MTCX-1.8TSSOP16StatusFull productionN/AN/A 1K+$2.95reel
of
2500		NSZXYTT
2651MTC
-1.8
14-16 weeks25000
LM2651MTCX-2.5TSSOP16StatusFull productionN/AN/A 
Buy Now		1K+$2.95reel
of
2500		NSZXYTT
2651MTC
-2.5
13-15 weeks25000
LM2651MTCX-3.3TSSOP16StatusFull productionN/AN/A 1K+$2.95reel
of
2500		NSZXYTT
2651MTC
-3.3
14-16 weeks25000
LM2651MTCX-ADJTSSOP16StatusFull productionN/AN/A 
Buy Now		1K+$2.95reel
of
2500		NSZXYTT
2651MTC
-ADJ
14-16 weeks25000
LM2651-1.8 MDCUnpackaged DieFull productionN/AN/ASamples  tray
of
N/A		-
N/A0
LM2651-3.3 MDCUnpackaged DieFull productionN/AN/ASamples  tray
of
N/A		-
N/A0
LM2651-ADJ MDCUnpackaged DieFull productionN/AN/ASamples  tray
of
N/A		-
N/A0
LM2651-1.8 MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0
LM2651-3.3 MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0
LM2651-ADJ MWCWaferFull productionN/AN/A   wafer jar
of
N/A		-
N/A0

General Description

The LM2651 switching regulator provides high efficiency power conversion over a 100:1 load range (1.5A to 15mA). This feature makes the LM2651 an ideal fit in battery-powered applications that demand long battery life in both run and standby modes.

Synchronous rectification is used to achieve up to 97% efficiency. At light loads, the LM2651 enters a low power hysteretic or "sleep" mode to keep the efficiency high. In many applications, the efficiency still exceeds 80% at 15mA load. A shutdown pin is available to disable the LM2651 and reduce the supply current to less than 10µA.

The LM2651 contains a patented current sensing circuitry for current mode control. This feature eliminates the external current sensing resistor required by other current-mode DC-DC converters.

The LM2651 has a 300 kHz fixed frequency internal oscillator. The high oscillator frequency allows the use of extremely small, low profile components.

A programmable soft-start feature limits current surges from the input power supply at start up and provides a simple means of sequencing multiple power supplies.

Other protection features include input undervoltage lockout, current limiting, and thermal shutdown.

Features

  • Ultra high efficiency up to 97%
  • High efficiency over a 1.5A to milliamperes load range
  • 4V to 14V input voltage range
  • 1.8V, 2.5V, 3.3V, or ADJ output voltage
  • Internal MOSFET switch with low RDS(on) of 75m
  • 300kHz fixed frequency internal oscillator
  • 7µA shutdown current
  • Patented current sensing for current mode control
  • Input undervoltage lockout
  • Adjustable soft-start
  • Current limit and thermal shutdown
  • 16-pin TSSOP package

Applications

  • Personal digital assistants (PDAs)
  • Computer peripherals
  • Battery-powered devices
  • Handheld scanners
  • High efficiency 5V conversion

Reliability Metrics

Part Number Process Early Failure Rate - Rejects Sample Size (EFR) PPM * Rel. Rejects Device Hours Long Term Failure Rates (FITS) MTTF
LM2651-1.8 MDCABCD15001020000924003926125054
LM2651-1.8 MWCABCD15001020000924003926125054
LM2651-3.3 MDCABCD15001020000924003926125054
LM2651-3.3 MWCABCD15001020000924003926125054
LM2651-3.3EVALABCD15001020000924003926125054
LM2651-ADJ MDCABCD15001020000924003926125054
LM2651-ADJ MWCABCD15001020000924003926125054
LM2651EVALABCD15001020000924003926125054
LM2651MTC-1.8ABCD15001020000924003926125054
LM2651MTC-2.5ABCD15001020000924003926125054
LM2651MTC-3.3ABCD15001020000924003926125054
LM2651MTC-ADJABCD15001020000924003926125054
LM2651MTCX-1.8ABCD15001020000924003926125054
LM2651MTCX-2.5ABCD15001020000924003926125054
LM2651MTCX-3.3ABCD15001020000924003926125054
LM2651MTCX-ADJABCD15001020000924003926125054

For more information on Reliablitity Metrics, please click here.


Application Notes

TitleSize in KbytesDate
View Online
Download
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AN-1143: Application Note 1143 LM2651_3.3V_EVAL 1.5A High Efficiency Synchronous Switching Regulator Evaluation Board 285 Kbytes 25-Sep-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-1197: Application Note 1197 Selecting Inductors for Buck Converters 371 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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