CURRENT RESONANT POWER SUPPLY DEVICE

摘要

First and second switch are connected in series to both terminals of a DC power source. A series circuit comprising a reactor, a primary winding of a transformer, and a capacitor connected in series, and is connected to a node between the first and second switches and one terminal of the DC power source. A rectifier smoothing circuit rectifies and smoothens a voltage generated across a secondary winding of the transformer and outputs a DC voltage. A control circuit alternately turns the first and second switches on and off. A voltage detection circuit detects the DC voltage from the rectifier smoothing circuit. A signal generation circuit generates a feedback signal from the DC voltage detected by the voltage detection circuit, and outputs the signal for turning the first and second switches on and off. A load current detection circuit detects load current contained in resonance current flowing through the capacitor.

主权项

1. A current resonant power supply device comprising:
a first switch and a second switch connected in series to both terminals of a DC power source; a series circuit comprising a reactor, a primary winding of a transformer, and a capacitor connected in series, and connected to a node between the first and second switches and one terminal of the DC power source; a rectifier smoothing circuit that rectifies and smoothens a voltage generated across a secondary winding of the transformer and outputs a DC voltage; a control circuit that alternately turns the first and second switches on and off; a voltage detection circuit that detects the DC voltage from the rectifier smoothing circuit; a signal generation circuit that generates a feedback signal based on the DC voltage detected by the voltage detection circuit, and outputs the feedback signal, the feedback signal being for turning the first and second switches on and off; a load current detection circuit that detects load current contained in resonance current flowing through the capacitor; a standby state detection circuit that detects a standby state based on the load current detected by the load current detection circuit and a standby threshold; and a burst oscillation circuit that operates the first and second switches in a burst oscillation mode based on the feedback signal if the standby state is detected.