Patent ID: 9560701
Date: 2017-01-31
CPC Classifications: H02M,H05B,Y02B

Claim:
1. A driving circuit, comprising: a first bridge circuit, wherein the first bridge circuit is coupled to an AC voltage source to output a first voltage, and the first bridge circuit comprises a first positive input terminal, a first negative input terminal, a first positive output terminal and a first negative output terminal; a second bridge circuit, wherein the second bridge circuit is coupled to the AC voltage source to output a second voltage, and the second bridge circuit comprises a second positive input terminal, a second negative input terminal, a second positive output terminal and a second negative output terminal, wherein the second negative output terminal and the first negative output terminal are coupled to the same ground potential; a first protection device coupled between the second positive input terminal and the AC voltage source, wherein the first protection device comprises a first capacitor and a first diode connected to the first capacitor; and a second protection device coupled between the second negative input terminal and the AC voltage source, wherein the second protection device comprises a second capacitor and a second diode connected to the second capacitor, wherein the first capacitor and the second capacitor are polarized, a cathode of the first capacitor is directly connected to an anode of the first diode and the second positive input terminal of the second bridge circuit, an anode of the first capacitor is directly connected to a cathode of the first diode, a cathode of the second capacitor is directly connected to an anode of the second diode and the second negative input terminal of the second bridge circuit, and an anode of the second capacitor is directly connected to a cathode of the second diode; wherein the first protection device and the second protection device are configured for avoiding that an input current inputted from the first positive input terminal or the first negative input terminal of the first bridge circuit is fed back to the second positive input terminal or the second negative input terminal of the second bridge circuit.