Patent ID: 9252669
Filing Date: 2016-02-02
CPC Classification: H02M

Claim Text:
1. An Alternating Current/Direct Current (AC/DC) converter, receiving an Alternating Current (AC) voltage through a concentric plug and converting the AC voltage into a Direct Current (DC) voltage, comprising: a Live (L) line and a Neutral (N) line, to which the AC voltage is applied; a filter circuit, comprising at least one capacitor disposed between the L line and the N line, and filtering the AC voltage; a rectifier and smoothing circuit, rectifying and smoothing an output of the filter circuit; and a Direct Current/Direct Current (DC/DC) converter, receiving an output voltage of the rectifier and smoothing circuit to generate a DC voltage; wherein the DC/DC converter comprises: an output capacitor; a first diode, having a cathode connected to the output capacitor; a second diode, having a cathode connected to a capacitor; a transformer, comprising a primary coil connected to an output terminal of the rectifier and smoothing circuit, a secondary coil connected to an anode of the first diode, and an auxiliary coil connected to an anode of the second diode; a switching transistor, connected to the primary coil; a control circuit, controlling the switching transistor; and a wave detection circuit, generating a wave detection voltage corresponding to an input voltage of the rectifier and smoothing circuit; wherein the control circuit comprises: a power supply terminal, connected to the cathode of the second diode and receiving a power supply voltage based on the DC voltage from the auxiliary coil; a ground terminal, grounded when in a use state; a first discharge terminal, connected to the N line without passing through the wave detection circuit; a first discharge path, disposed on a path from the first discharge terminal to the ground terminal and comprising: a first discharge switch, disposed between the power supply terminal and the ground terminal; and a second discharge switch, disposed between the first discharge terminal and the power supply terminal; a detection terminal, receiving the wave detection voltage generated by the wave detection circuit; and first threshold voltage, and enabling the first discharge path to be turned on; wherein the control circuit is structured to: