The UC3844B, UC3845B series are high performance fixed frequency current mode controllers. They are specifically designed for OffLine and dctodc converter applications offering the designer a costeffective solution with minimal external components. These integrated circuits feature an oscillator, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET. Also included are protective features consisting of input and reference undervoltage lockouts each with hysteresis, cyclebycycle current limiting, a latch for single pulse metering, and a flipflop which blanks the output off every other oscillator cycle, allowing output deadtimes to be programmed from 50% to 70%.