VPC5021

The VPC5021 offline pulse width modulation (PWM) controller adopts current mode control to achieve the application of efficient offline single ended flyback/forward power converter. The VIN high-voltage power supply port achieves ultra-low startup current (less than 5uA), startup voltage of 20V, undervoltage locking voltage of 7.6V, and minimizes the power consumption of the startup network under a certain startup time, achieving a low standby power consumption ACDC power converter. The starting voltage of the VDD low-voltage power supply port is as low as 7.4V, which can also meet the application of low input voltage DCDC switching power supplies. The VPC5021 controller operates at a fixed maximum operating frequency for PWM modulation under heavy loads. As the load is reduced to a certain extent, the controller optimizes the efficiency of the full load range by gradually simulating the frequency reduction mode, while obtaining lower light load ripple voltage and no-load power consumption without audio noise. This effectively solves the contradiction between no-load power consumption, light load ripple, and audio noise. VPC5021 also integrates functions such as output short circuit protection, overcurrent protection, and output overvoltage protection, ensuring high reliability of the switching power supply across the entire range.