DataSheet.
in
UTC UC3842A / 3843A LINEAR INTEGRATED CIRCUIT
CURRENT MODE PWM CONTROL CIRCUITS
DESCRIPTION
The UTC UC3842A/3843A provide the necessary functions to implement off-line or DC to DC fixed frequency current mode , controlled switching circuits with a minimal external part count
SOP-8
FEATURES
*Low external part count.
*Low start up current ( Typical 0.
12mA ) *Automatic feed forward compensation *Pulse-by-Pulse current limiting *Under-
voltage lockout with hysteresis *Double pulse Suppression *High current totem pole output to drive
MOSFET directly *Internally trimmed band gap reference *500kHz operation
DIP-8
BLOCK DIAGRAM
7
Vcc
Vref
8
Internal Bias 1/2Vref
5V REF
S/R
5 GND...