TI intermediate bus PWM controller increases energy efficiency over entire load range

The integrated UCC28230 PWM controller supports both the half-bridge and full-bridge topologies and reduces overall size and the need for external components. Designers can set the operation to work in a fixed volt-second or fixed frequency mode, which reduces the size of the transformer.

The UCC28230 has a start-up frequency control feature that limits output inductor ripple current, allowing the use of a smaller, inexpensive inductor. The UCC28230 implements load-dependent dead-time control to improve efficiency over the entire output load range. It also has 1-D output that shorts the primary-side winding, which keeps the self-driven synchronous rectifiers under control during start-up and shut-down and through transient conditions. Additionally, the UCC28230 provides state-of-the-art protection features, such as input under-voltage lockout, thermal shutdown protection and cycle-by-cycle over-current protection.

The UCC28230 includes a precision 5-V reference voltage output for general-purpose voltage biasing. In addition, the UCC28231 includes a precision 3.3-V reference voltage output for the same purpose. For added flexibility, the controller can be paired with TI’s UCC27200 dual high-side, low-side driver to drive MOSFETs for half- and full-bridge topologies.

The UCC28230 intermediate bus controller can also be used in high-voltage applications such as DC/DC transformers, and it serves as a downstream converter when paired with TI’s UCC28070 interleaved PFC controller.