UCC28064A (ACTIVE) Natural Interleaving™ transition-mode PFC controller with high light-load efficiency

The UCC28064A interleaved PFC controller has higher power ratings than previously possible. The device uses a Natural Interleaving™ technique. Both channels operate as masters (there is no slave channel) synchronized to the same frequency. This approach enables faster response time, excellent phase-to-phase on-time matching, and transition mode operation for each channel. The device has a burst mode function to get high light-load efficiency. Burst mode eliminates the need to turn off the PFC during light load operation to meet standby power targets. Burst mode eliminates the need for an auxiliary flyback converter when paired with UCC25630x LLC controller and the UCC24624 synchronous rectifier controller.

Expanded system level protections features include input brownout and dropout recovery, output over-voltage, open-loop, overload, soft-start, phase-fail detection, and thermal shutdown. The additional fail-safe over-voltage protection (OVP) feature protects against shorts to an intermediate voltage that, if undetected, could lead to catastrophic device failure. Advanced non-linear gain results in rapid, yet smooth response to line and load transient events. Special line-dropout handling avoids significant current disruption. Strong reduction of bias current when not switching during burst mode operation, improves stand-by performance.