KA3882E Datasheet, PDF (1/6 Pages) Fairchild Semiconductor – SMPS Controller

KA3882E/KA3883E
SMPS Controller
www.fairchildsemi.com
Features
• Low start current 0.2mA (typ)
• Operating range up to 500kHz
• Cycle by cycle current limiting
• Under voltage lock out with hysteresis
• Short shutdown delay time: typ.100ns
• High current totem-pole output
• Output swing limiting: 22V
Description
The KA3882E/KA3883E is a fixed PWM controller for
Off-Line and DC to DC converter applications. The internal
circuits include a UVLO, a low start-up current circuit, a
temperature compensated reference, a high gain error
amplifier, a current sensing comparator, and the high current
totem-pole output for driving a POWER MOSFET. Also the
KA3882E/KA3883E provides low start-up current below
0.3mA and short shutdown delay time typ. 100ns. The
KA3882E has UVLO threshold of 16V(on) and 10V(off).
The KA3883E is 8.4V(on) and 7.6V(off). The KA3882E and
KA3883E can operate within 100% duty cycle.
8-DIP
1
8-SOP
1
Internal Block Diagram
VREF 8
Internal
Bias
5V
VREF
SET/
RESET
Good LOGIC
UVLO
VFB 2
COMP 1
1/2VREF
Error Amp
+
-
1/3
1V
C.S _PWM
Comp. _LATCH
R
S
C.S 3
T
RT/CT 4
OSCILLATOR
7 VCC
29V
5 GND
7
PWR
VC
22V 6 OUTPUT
5
PWR
GND
©2003 Fairchild Semiconductor Corporation
Rev. 1.0.1