Two-phase Interleaved CCM PFC controller with Extended Frequency Range (10kHz to 300kHz)

The UCC28070A and UCC28070 are advanced power factor correction (PFC) controllers that each integrate two pulse-width modulators (PWMs) operating interleaved by 180° in CCM boost-mode. Both devices can switch at frequencies up to 300kHz, while the UCC28070A device is capable of operating down to 10kHz for IGBT power-switch based PFC converters in high-power applications. The minimum operating frequency of the UCC28070 device is limited to 30kHz.

The 180° out-of-phase interleaved operation generates substantial reduction in input and output ripple currents and conducted-EMI filtering becomes easier and less expensive. All the other features and benefits of the UCC28070A and UCC28070 devices are the same.

Both devices feature multiple innovations including current synthesis and quantized voltage feedforward to promote performance enhancements in PF, efficiency, THD, and transient response. In addition, frequency dithering, clock synchronization, and slew-rate enhancement further expand the potential for performance improvements. Also, protection features include output overvoltage detection, programmable peak-current limit, undervoltage lockout, and open-loop protection.