The UCC28089D is a versatile BiCMOS Controller for DC to DC or off-line fixed-frequency switching power supplies. The UCC28089 has dual alternating output stages in dual-alternating push-pull configuration. Both outputs switch at half the oscillator frequency using a toggle flip-flop and duty cycle is limited to less than 50%. It is optimized for use as the primary-side companion controller for a cascaded converter that has secondary-side control. The device incorporates dead-time programming. The synchronization output also provides dead-time information. The retry and soft-start duration scales with the oscillator clock frequency for high performance fault recovery. It also provides primary side under-voltage protection (UVLO) and over-current protection. Both the soft start and retry after fault durations scale with oscillator frequency for high performance. The turn-on/off UVLO thresholds are 10.5/8V.
Push-pull oscillator with programmable deadtime
Can be used in push-pull, half-bridge, or full-bridge topologies
