Current Mode PWM Controller UC3845B

The Current Mode Pwm Controller UC3845B is a high performance fixed frequency current mode controller. This current mode PWM is specifically designed for Off-Line and dc-to-dc converter applications offering the designer a cost-effective solution with minimal external components. This PWM controller features 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 under-voltage lockouts each with hysteresis, cycle-by-cycle current limiting, a latch for single pulse metering, and a flip-flop which blanks the output of every other oscillator cycle, allowing output deadtimes to be programmed from 50% to 70%.