UC3844D

The UC3844D is a current-mode Pulse Width Modulation (PWM) Controller provides the necessary features to implement off-line or DC to DC fixed frequency current-mode control schemes with a minimal external parts count. Internally implemented circuits include under-voltage lockout featuring start up current less than 1mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-channel MOSFETs, is low in the off state. Differences between members of this family are the under-voltage lockout thresholds and maximum duty cycle ranges. It is ideally suited to off-line applications.