AND8331D_ACDC_转化器IC参考资料.pdf

AND8331/D Quasi-Resonant Current- Mode Controller for High- Power ac-dc Adapters Prepared by: Stéphanie Conseil ON Semiconductor Introduction Pin Description This document describes the implementation of the Over Power Protection pin (OPP, pin 1): applying a DAP013 inside an AC-DC adapter. negative voltage on this pin reduces the internal maximum The DAP013 offers everything to build high performance peak current set point. AC-DC converters or offline adapters. Thanks to a novel Over Temperature Protection pin (OTP, pin 2): Connect valley lockout system, the controller is able to switch inside an NTC between this pin and ground. An internal current the drain-source valley and is immune to valley jumping source biases the NTC. When the NTC pulls the pin down, instabilities. When the output load decreases significantly, the circuit permanently latches-off. the controller toggles to a fixed peak current/variable Timer pin (Timer, pin 3): Wiring a capacitor from this pin frequency mode that ensures very low standby power to ground helps selecting the timer duration. consumption. And last, but not least, the DAP013 features Zero Voltage Detection pin (ZCD, pin 4): Connected to the usual protections that help to build cheap and safe power the auxiliary winding, this pin detects the core reset event. supplies: OVP, OTP, Brown-Out (C and D options), Timing Capacitor pin (Ct, pin 5): A capacitor connected Short-circuit protection (latched for A, C versions and to this pin acts as the timing capacitor in VCO mode. auto-recovery for D, F vers