Phase-shifted full-bridge controller for wide input voltage range

The Texas Instruments UCC28951 device is an enhanced version of the UCC28950. It is a fully compatible drop-in replacement for the device. The device uses advanced control of the full-bridge as well as active control of the synchronous rectifier output stage. Programmable delays secure ZVS operation over a broad range of operating conditions, while the load current naturally tunes the switching delays of the secondary-side synchronous rectifiers. This functionality maximises overall system efficiency. The device has many light-load management features including burst-mode operation and dynamic SR ON and OFF control throughout transition into and out of discontinuous current mode operation. The device works in current-mode or voltage-mode control. The switching frequency can be programmed up to 1MHz. The device has protection features including cycle-by-cycle current limit, UVLO, and thermal shutdown. The 24-pin, TSSOP package complies with RoHS requirements.