Two-phase Interleaved continuous conduction mode (CCM) PFC controller

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.