UCC28780 is a high-frequency active-clamp flyback controller that enables high-density
AC-to-DC power supplies that comply with stringent global efficiency standards such as DoE Level VI
and EU CoC V5 Tier-2. User programmable advanced control law features allow performance to be
optimized for both Silicon (Si) and Gallium Nitride (GaN) power FETs. Direct operation with
switching devices that combine driver and GaN FETs is further enhanced with logic-level gate
signals and enable outputs.
Zero voltage switching (ZVS) is achieved over a wide operating range with advanced
auto-tuning techniques, adaptive dead-time optimization, and variable switching frequency control
law. Using adaptive multimode control that changes the operation based on input and output
conditions, UCC28780 enables high efficiency while mitigating audible noise. With a variable
switching frequency of up to 1 MHz and accurate programmable over-power protection, which provides
consistent power for thermal design across wide line range, the size of passive components can be
further reduced and enable high power density.
UCC28780 works with VDS-sensing synchronous rectifier controllers, such as
UCC24612, to achieve higher conversion efficiency and
very compact designs.