UC3842 Datasheet - ST Microelectronics

UC3842, CURRENTMODE PWM CONTROLLER

® UC2842/3/4/5 UC3842/3/4/5 CURRENT MODE PWM CONTROLLER * *.
OPTIMIZED FOR OFF-LINE AND DC TO DC CONVERTERS LOW START-UP CURRENT (<

Features

* to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal externalparts count. Internallyimplementedcircuits include undervoltagelockout featuring start-up current less than 1 mA, a precision reference trimmed for accuracy at the error amp input, logic to insure l

Applications

* The corresponding thresholds for the UC3843 and UC3845 are 8.5 V and 7.9 V. The UC3842 and UC3843 can operate to duty cycles approaching 100%. A range of the zero to < 50 % is obtained by the UC3844 and UC3845 by the additionof an internal toggle flip flop which blanks the output off every other clo

UC3842_STMicroelectronics.pdf