www.fairchildsemi.com
FS6X1220R
Features
Fairchild Power Switch (FPS
TM
)
Description
The FS6X1220R is specially designed for an off-line DC-
DC converters with minimal external components. This
device is a current mode PWM controller combined with a high
voltage power SenseFET in a single package. The PWM
controller includes integrated fixed frequency oscillator, line
under voltage lockout, sleep on/off function, thermal
shutdown protection, over voltage protection, pulse-by-pulse
current limit and temperature compensated precise current
sources for a loop compensation. Compared with discrete
MOSFET and PWM controller solution, the FS6X1220R can
reduce total cost, component count, size and weight simulta-
neously increasing efficiency, productivity, and system
reliability. This device is well suited for DC to DC converter
applications up to 40W of output power.
TO-220F-5L
D2-PAK-5L
鈥?Current Mode PWM Control With a Fixed Operating
Frequency (300kHz)
鈥?Pulse by Pulse Current Limit
鈥?Over Load Protection
鈥?Over Voltage Protection
鈥?Thermal Shutdown
鈥?Built-in Auto-Restart Circuit
鈥?Line Under Voltage Detection and Sleep on/off Function
鈥?Internal High Voltage SenseFET (QFET)
鈥?Supports Forward or Flyback Topology
Application
鈥?DC-DC Converter
1
1. Drain 2. GND 3. V
CC
4. Feedback 5. Line Sense
Internal Block Diagram
Vcc
3
V
LU
Line UVLO
Vcc good
9V/15V
Drain
1
Line
5
Sense
V
SL
Vcc
I
delay
Vref
I
FB
28R
OSC
Enable
Vref
Internal
Bias
S
Q
FB 4
R
V
SD
Vcc
S
R
Q
Gate driver
Q
Vovp
TSD
Line UVLO
Vcc good
R
Q
2 GND
Rev.1.0.1
漏2004 Fairchild Semiconductor Corporation