The UCC2897A PWM controller simplifies implementation of the various active clamp or reset and synchronous rectifier switching power topologies. The UCC2897A is a peak current-mode fixed-frequency high-performance pulse-width modulator. The controller includes the logic and the drive capability for the P-channel auxiliary switch along with a simple method of programming the critical delays for proper active-clamp operation. Features include an internal programmable slope compensation circuit, precise DMAX limit, and a synchronizable oscillator with an internal-timing capacitor. An accurate line-monitoring function also programs the ON and OFF transitions of the converter with regard to the bulk input voltage, VIN. The UCC2897A adds a second-level hiccup-mode current-sense threshold, bi-directional synchronization and input-overvoltage protection functionalities. The UCC2897A is offered in 20-pin TSSOP (PW) and 20-pin QFN (RGP) packages.