Synchronous Rectifier Controller with Zero Voltage Switching for Wide Output Voltage Operating Range

The RT7220D is a Synchronous Rectifier (SR) controller for Flyback converters operating in Continuous Conduction Mode (CCM), Discontinuous Conduction Mode (DCM) and Quasi-Resonant (QR) mode. The RT7220D will sense the drain voltage of MOSFET to determine SR gate on/off so as to minimize turn-off dead-time and enhance efficiency. The RT7220D supports the wide output voltage range from 3V to 21V, and a HV LDO is especially built-in for the MOSFET gate driver at low output voltage. When it works with the primary-side controller RT7757, the Zero-Voltage-Switching (ZVS) control can be enabled to optimize the efficiency at high line.Furthermore, the RT7220D provides a green mode operation in light load condition, which reduces operation current to be under 250μA.The recommended junction temperature range is -40°C to 125°C, and the ambient temperature range is -40°C to 105°C.