©2003 Fairchild Semiconductor Corporation

www.fairchildsemi.com

Rev.1.0.6

Features

• Precision Fixed Operating Frequency (100/67/50kHz)

• Low Start-up Current(Typ. 100uA)

• Pulse by Pulse Current Limiting

• Over Current Protection

• Over Voltage Protection (Min. 25V)

• Internal Thermal Shutdown Function

• Under Voltage Lockout

• Internal High Voltage Sense FET

• Auto-Restart Mode

Applications

• SMPS for VCR, SVR, STB, DVD & DVCD

• SMPS for Printer, Facsimile & Scanner

• Adaptor for Camcorder

Description

The Fairchild Power Switch(FPS) product family is specially

designed for an off-line SMPS with minimal external

components. The Fairchild Power Switch(FPS) consists of a

high voltage power SenseFET and a current mode PWM IC.

Included PWM controller integrates the fixed frequency

oscillator, the under voltage lock-out, the leading edge

blanking, the optimized gate turn-on/turn-off driver, the

thermal shutdown protection, the over voltage protection,

and the temperature compensated precision current sources

for the loop compensation and the fault protection circuitry.

Compared to a discrete MOSFET and a PWM controller or

an RCCsolution, a Fairchild Power Switch(FPS) can reduce

the total component count, design size and weight and at the

same time increase efficiency, productivity, and system

reliability. It has a basic platform well suited for the cost

effective design in either a flyback converter or a forward

converter

Internal Block Diagram

32V

5

µA

9V

2.5R

1R

1mA

0.1V

+

−

OVER VOLTAGE S/D

+

−

7.5V

27V

Thermal S/D

S

R

Q

Power on reset

+

−

L.E.B

S

R

Q

OSC

5V

Vref

Internal

bias

Good

logic

SFET

#2 DRAIN

#1 GND

#4 FB

KA5x03xx-SERIES

KA5H0365R, KA5M0365R, KA5L0365R

KA5H0380R, KA5M0380R, KA5L0380R

Fairchild Power Switch(FPS)

TO-220F-4L

1