
©2003 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev.1.0.2
Features
• Precision Fixed Operating Frequency
• KA1M0280RB (67kHz) , KA1 H02 80R B ( 100kHz)
• Pulse by Pulse Over Current Limiting
• Over Load Protectio n
• Over Voltage Protection (Min. 23V)
• Internal Thermal Shutdown Function
• Unde r Voltage Lo ck out
• Internal High Voltage Sense FET
•Auto Restart
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)
consist of high
voltage power SenseFET and current mode PWM controller IC.
PWM controller features integrated fixed oscillator, under
voltage lock out, leading edge bl anking, optimized gate turn-on /
turn-of f driver, thermal shut down protection, over voltage
protection, temperature compensated precision current sources
for loop compensation and fault protection circuit. compared to
discrete MOSFET and controller or R
CC
switching converter
solution, a
Fairchild Power Switch(FPS)
can reduce total
component count, design size, weight and at the same time
increase & efficiency, productivity, and system reliability. It has
a basic platform well suited for cost effective design in either a
flyback converter or a forward converter.
TO-220F-4L
1. GND 2. DRAIN 3. VCC 4. FB
1
Internal Block Diagram
#3 V
CC
32V
5
µ
A9V
2.5R
1R
1mA
0.1V
+
−
OVER VOLTAGE S/D
+
−
7.5V
25V
Thermal S/D
S
RQ
Power on reset
+
−
L.E.B
S
RQ
OSC
5V
Vref Internal
bias
Good
logic
SFET #2 DRAIN
#1 GND
#4 FB
KA1M0280RB/KA1H0280RB
Fairchil d Power Swi tch(FPS)