UCC2891D (TEXAS INSTRUMENTS)

The UCC2891D is a current-mode active clamp Pulse Width Modulation (PWM) Controller designed to simplify implementation of the various active clamp/reset switching power topologies. It is a peak current-mode, fixed frequency, high-performance pulse width modulator. It includes the logic and the drive capability for the auxiliary switch with a simple method of programming the critical delays for proper active clamp operation. It includes a 110V start-up regulator for initial start-up and to provide keep-alive power during stand-by. Additional features include an internal programmable slope compensation circuit, precise DMAX limit and a single resistor programmable synchronizable oscillator. An accurate line monitoring function also programs the converter's ON and OFF transitions with regard to the bulk input voltage.