700V Flyback switcher with constant-voltage constant-current and primary-side regulation

The UCC28910 and UCC28911 are high-voltage flyback switchers that provide output voltageand current regulation without the use of an optical coupler. Both devices incorporate a 700-Vpower FET and a controller that process operating information from the flyback auxiliary windingand power FET to provide a precise output voltage and current control. The integrated high-voltage current source for startup that is switched off during device operation, and the controller current consumption is dynamically adjusted with load. Both enablethe very low stand-by power consumption.

Control algorithms in the UCC28910 and UCC28911, combining switching frequency and peakprimary current modulation, allow operating efficiencies to meet or exceed applicable standards.Discontinuous conduction mode (DCM) with valley switching is used to reduce switching losses.Built-in protection features help to keep secondary and primary component stress levels in check across the operating range. The frequency jitter helps to reduce EMI filter