Texas Instruments has designed PWM power supply controllers with integrated, programmable-delay synchronous rectifier control outputs and pre-bias start-up circuitry.
As a result, the UCC28250 is TI’s first half bridge or full bridge PWM controller which will maintain a monotonic output voltage ramp under pre-biased load conditions, without the need for external circuitry.
This means it can be used to in primary- or secondary-side control circuits and will deliver up to 95% efficiency and high power density in high-input voltage isolated DC-DC applications, such as power modules used in wireless base stations or industrial power systems.
The devices support multiple high-frequency topologies, such as half-bridge, full-bridge, interleaved forward and push-pull, that may have stringent pre-bias start-up requirements and support multiple high-efficiency topologies.
A second device, the UCC28950, has two additional PWM outputs for phase-shifted full bridge control up to 600W with 90% efficiency.
As well as synchronous rectifier control, it provides adaptive zero voltage switching over a wide input and output voltage range to reduce switching loss.
