Synchronous rectification type power circuit and method of adjusting the same

摘要

According to one embodiment, a synchronous rectification type power circuit includes a first power terminal to which a voltage on a high potential side is supplied, a second power terminal to which a voltage on a low potential side is supplied, an output terminal that outputs an output voltage to a load having an inductance and a capacitor, a first switch unit connected between the first power terminal and the output terminal, a second switch unit connected between the second power terminal and the output terminal, a control signal generating circuit which controls ON/OFF of the first and second switch units, and a control circuit that compares the output voltage with a predetermined reference voltage for a predetermined period when the second switch unit is turned OFF. A timing for turning OFF the second switch unit is adjusted based on a result of the comparison.

主权项

1. A synchronous rectification type power circuit comprising:
a first power terminal to which a voltage on a high potential side is supplied; a second power terminal to which a voltage on a low potential side is supplied; an output terminal that outputs an output voltage to a load having an inductor and a capacitor; a first switch connected between the first power terminal and the output terminal; a second switch connected between the second power terminal and the output terminal; a control circuit that controls ON/OFF of the first and second switches; and a detecting circuit that compares the output voltage with a predetermined reference voltage for a predetermined period from a time when the second switch is turned OFF and that adjusts a circuit threshold based on a result of the comparison, wherein the control circuit delays a timing at which the second switch is turned OFF when the detecting circuit detects that the output voltage is lower than the predetermined reference voltage and quickens the timing at which the second switch is turned OFF when the detecting circuit detects that the output voltage is higher than the predetermined reference voltage.