LM2622

600kHz/1.3MHz Step-up PWM DC/DC Converter

General Description

The LM2622 is a step-up DC/DC converter with a 1.6A, 0.2

Ω

internal switch and pin selectable operating frequency. With

the ability to convert 3.3V to multiple outputs of 8V, -8V, and

23V, the LM2622 is an ideal part for biasing TFT displays.

The LM2622 can be operated at switching frequencies of

600kHz and 1.3MHz 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

LM2622 is available in a low profile 8-lead MSOP package.

Features

n

1.6A, 0.2

Ω, internal switch

n

Operating voltage as low as 2.0V

n

600kHz/1.3MHz pin selectable frequency operation

n

Over temperature protection

n

8-Lead MSOP package

Applications

n

TFT Bias Supplies

n

Handheld Devices

n

Portable Applications

n

GSM/CDMA Phones

n

Digital Cameras

Typical Application Circuit

10127331

600 kHz Operation

May 2004

© 2004 National Semiconductor Corporation

DS101273

www.national.com