Switching circuit and operating method

The invention discloses a switching circuit and an operation method. The switching circuit comprises a live wire power taking circuit, a control circuit and a controllable capacitor array. The live wire power taking circuit is coupled to a live wire to receive an AC voltage. The control circuit is used for carrying out zero-crossing detection on the alternating-current voltage. The controllable capacitor array is coupled to the live wire power taking circuit and the control circuit. The control circuit is used for controlling the live wire power taking circuit to supply power to the control circuit or controlling the controllable capacitor array to discharge so as to supply power to the control circuit based on the state of a first switch and a zero-crossing detection result. 一种开关电路以及运行方法。开关电路包含一火线取电电路、一控制电路以及一可控电容阵列。火线取电电路耦接一火线以接收一交流电压。控制电路用以对交流电压进行一过零检测。可控电容阵列耦接火线取电电路以及控制电路。控制电路用以基于一第一开关的状态以及一过零检测结果，控制火线取电电路供电给控制电路或可控电容阵列放电以对控制电路供电。