LM2700

600kHz/1.25MHz, 2.5A, Step-up PWM DC/DC Converter

General Description

The LM2700 is a step-up DC/DC converter with a 3.6A,

80m

Ω internal switch and pin selectable operating fre-

quency. With the ability to produce 500mA at 8V from a

single Lithium Ion battery, the LM2700 is an ideal part for

biasing LCD displays. The LM2700 can be operated at

switching frequencies of 600kHz and 1.25MHz allowing for

easy filtering and low noise. An external compensation pin

gives the user flexibility in setting frequency compensation,

which makes possible the use of small, low ESR ceramic

capacitors at the output. The LM2700 features continuous

switching at light loads and operates with a switching quies-

cent current of 2.0mA at 600kHz and 3.0mA at 1.25MHz. The

LM2700 is available in a low profile 14-lead TSSOP package

or a 14-lead LLP package.

Features

n

3.6A, 0.08

Ω, internal switch

n

Operating input voltage range of 2.2V to 12V

n

Input undervoltage protection

n

Adjustable output voltage up to 17.5V

n

600kHz/1.25MHz pin selectable frequency operation

n

Over temperature protection

n

Small 14-Lead TSSOP or LLP package

Applications

n

LCD Bias Supplies

n

Handheld Devices

n

Portable Applications

n

GSM/CDMA Phones

n

Digital Cameras

Typical Application Circuit

20012301

600 kHz Operation

May 2004

© 2004 National Semiconductor Corporation

DS200123

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