FLYBACK POWER CONVERTER HAVING A CONSTANT VOLTAGE AND A CONSTANT CURRENT OUTPUT UNDER PRIMARY-SIDE PWM CONTROL
摘要
<p>A primary-side flyback power converter supplies a constant voltage and a constant current output. To generate a well-regulated output voltage under varying load conditions, the power converter includes a PWM controller. The PWM controller generates a PWM signal to control a switching transistor in response to a flyback voltage detected from the first primary winding of the power supply transformer. To reduce power consumption, the flyback energy of the first primary winding is used as a DC power source for the PWM controller. The flyback voltage is sampled following a delay time to reduce interference from the inductance leakage of the transformer. To generate a more accurate DC output voltage, a bias current is pulled from the detection input to form a voltage drop across a detection resistor for compensating for the voltage drop of the output rectifying diode.</p>
申请公布号
WO2004112226(A1)
申请公布日期
2004.12.23
申请号
WO2004CN00653
申请日期
2004.06.18
申请人
SYSTEM GENERAL CORP.;YANG, TA-YUNG;CHEN, CHERN-LIN;LIN, JENN-YU G.;LIN, SONG-YI