Patent ID: 9479069
Filing Date: 2016-10-25
CPC Classification: H02M

Claim Text:
1. A power conversion apparatus, comprising: a flyback power conversion circuit, configured to receive an alternating current (AC) input voltage and convert the AC input voltage in response to a pulse width modulation (PWM) signal, and thereby generating and providing a direct current (DC) output voltage; a control chip, coupled to the flyback power conversion circuit, and generating the PWM signal in response to a power supply requirement to control operations of the flyback power conversion circuit, wherein the control chip has one multi-function detection pin; and a detection auxiliary circuit, coupled to the flyback power conversion circuit and the multi-function detection pin of the control chip, wherein the detection auxiliary circuit assists the control chip to obtain an auxiliary voltage related to the DC output voltage via the multi-function detection pin, and thereby determines a transition time of the PWM signal according to a comparison result of the auxiliary voltage and a reference valley voltage, wherein the detection auxiliary circuit assists the control chip to execute a detection of an over temperature protection via the multi-function detection pin within a first detection phase, and assists the control chip to execute a detection of an over voltage protection via the multi-function detection pin within a second detection phase.