LM2621 - Low Input Voltage, Step-Up DC-DC
Datasheet Packaging Samples & Pricing Eval. Boards Reliability Design Tools Reference Designs Application Notes Knowledge Base

Features
•Small Mini-SO8 Package (Half the Footprint of Standard 8-Pin SO Package)
•1.09 mm Package Height
•Up to 2 MHz Switching Frequency
•1.2V to 14V Input Voltage
•1.24V - 14V Adjustable Output Voltage
•Up to 1A Load Current
•0.17 Internal MOSFET
•Up to 90% Regulator Efficiency
•80 µA Typical Operating Current
•<2.5µA Guaranteed Supply Current In Shutdown

General Description

The LM2621 is a high efficiency, step-up DC-DC switching regulator for battery-powered and low input voltage systems. More...


Applications

•PDAs, Cellular Phones
•2-Cell and 3-Cell Battery-Operated Equipment
•PCMCIA Cards, Memory Cards
•Flash Memory Programming
•TFT/LCD Applications
•3.3V to 5.0V Conversion
•GPS Devices
•Two-Way Pagers
•Palmtop Computers
•Hand-Held Instruments
  Typical Application
click for larger image


ParametersValues
Output Range 1.24V to 14V
Switch Current 2.85 Amp
Input Min Voltage 1.2 Volt
Input Max Voltage 14 Volt
Frequency Max 2000 kHz
Output Min 1.24 Volt
Output Max 14 Volt
Efficiency (peak) 90 %
Sync Pin No
Adj Switch Frequency Yes
Frequency Min 300 kHz
On/Off Pin Yes
Error Flag No
SoftStart No
Special Features Constant duty cycle gated oscillator
PWM Mode Gated Oscillator
Topology Boost, Flyback
Step-Up Yes
Inverting No
Flyback Yes
RegType Switching Regulator
Adjustable Output Yes
Output Power Undefined Watt
Temperature Min -40 deg C
Temperature Max 85 deg C


Typical Performance

click for larger image


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LM2621
 
1.20 <=		 V in Lower
 V		  
<=		 V in Upper
 V		  
<= 14.00
V out 1.24 <=  V <= 14.00
I out    A <= 2.85
Ambient Temperature  °C <= 100


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Also Recommended
LM2623▲Operates With Input Voltages As Low As 0.8V
LM2698▲Wider Switch Voltage , Fixed Frequency
LM27313▲Fixed Frequency , Smaller Package
LM2733▲1A 40V Switch Boost Regulator In SOT-23
LM3224▲Wider Switch Voltage , Fixed Frequency
LM2704Low Power 500mA Switch Boost In SOT-23
Additional Resources
Design Tools

Application Notes


Connection Diagram

click for larger image



Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LM2621 Low Input Voltage, Step-Up DC-DC Converter 656
Kbytes		 25-Mar-05 Download
LM2621 Low Input Voltage, Step-Up DC-DC Converter (Japanese)
 372 Kbytes   Download

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


Package Availability, Models, Samples & Pricing
Part NumberPackageFactory Lead TimeModelsSamples &
Electronic
Orders		Budgetary PricingStd
Pack
Size		Package
Marking
Format
TypePinsSpec.MSL
Rating		Peak
Reflow		RoHS
Report		CAD
Symbols		WeeksQtyQty$US each
LM2621EVALLow Input Voltage, Step-Up DC-DCFull productionN/A
 
Buy Now 		1+$30.001-
8 weeksN/A
LM2621MMMINI SOIC8NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.71reel
of
1000		ZXTT
S06A
6 weeks2000
LM2621MMXMINI SOIC8NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.71reel
of
3500		ZXTT
S06A
6 weeks5000

General Description

The LM2621 is a high efficiency, step-up DC-DC switching regulator for battery-powered and low input voltage systems. It accepts an input voltage between 1.2V and 14V and converts it into a regulated output voltage. The output voltage can be adjusted between 1.24V and 14V. It has an internal 0.17 N-Channel MOSFET power switch. Efficiencies up to 90% are achievable using the LM2621.

The high switching frequency (adjustable up to 2MHz) of the LM2621 allows for tiny surface mount inductors and capacitors. Because of the unique constant-duty-cycle gated oscillator topology very high efficiencies are realized over a wide load range. The supply current is reduced to 80µA because of the BiCMOS process technology. In the shutdown mode, the supply current is less than 2.5µA.

The LM2621 is available in a Mini-SO-8 package. This package uses half the board area of a standard 8-pin SO and has a height of just 1.09 mm.

Reliability Metrics

Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
LM2621MMABCD15003417500423400011201409060
LM2621MMXABCD15003417500423400011201409060

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.


Design Tools

TitleSize in Kbytes Date Click link below to Download    
Power Reference Design Library     View    

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Reference Designs
•LM2621 Reference Design - Sepic Converter for Battery Applications: 2.7-5.5V Input, 3.3V @ 0.65A Output

More Application Notes

TitleSize in Kbytes Date Click link below to Download
AN-1274: Application Note 1274 LM2623 Evaluation Board 636
Kbytes		 21-Sep-05 Download
AN-1274 (Chinese): Application Note 1274 LM2623 Evaluation Board
 208 Kbytes  
AN-1250: Application Note 1250 Inductive Based Switching Regulator Circuits Provide High Efficiency White LED Drives 81
Kbytes		 26-Sep-02 Download
AN-1237: Application Note 1237 RSDS™ Flat Panel Display Design Guidelines Part 2 141
Kbytes		 14-May-03 Download
AN-1258: Application Note 1258 National`s LM2623 Boost Converter - A Simple Supply 64
Kbytes		 2-May-04 Download
AN-1221: Application Note 1221 LM2623 Cookbook 35
Kbytes		 2-May-04 Download
AN-1221 (Japanese): Application Note 1221 LM2623 Cookbook
 60 Kbytes   Download
AN-1198: Application Note 1198 LM2622 Step-Up DC/DC Converter Evaluation Board 110
Kbytes		 3-Apr-07 Download

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

[Information as of 7-Nov-2009]