©2002 Fairchild Semiconductor Corporation

www.fairchildsemi.com

Rev. 1.0.1

Features

• Operation From 3.0 to 40V Input

• Short Circuit Current Limiting

• Low Stand-by Current

• Output Switch Current of 1.5A Without External

Transistors

• Output Voltage Adjustable

• Frequency of Operation From 100Hz to 100kHz

• Step-up, Step-Down or Inverting Switching Regulators

Description

The KA34063A is a monolithic regulator sub system

intended for use as DC to DC converter. This device

contains a temperature compensated bandgap reference, a

duty cycle control oscillator, a driver, and a high current

output switch. It can be used for step down, step up or

inverting switching regulators as well as for series pass

regulators.

8-DIP

8-SOP

1

1

Internal Block Diagram

5

1

8

2

7

3

4

COMP

OSCILLATOR

RD

Q2

Q1

S

Q

R

1.25V

REF

VTG

COMPARATOR

INVERTING

INPUT

DRIVE

COLLECTOR

SWITCH

COLLECTOR

GND

TIMING

CAPACITOR

KA34063A

SMPS Controller