Switching power supply with capacitor input for a wide range of AC input voltages

摘要

A switching power supply includes a bridge rectifier, a switching device, and a controller. The bridge rectifier is operatively coupled to an alternating current (ac) signal, and outputs a rectified signal. The switching device is electrically connected in parallel with the bridge rectifier. The controller is responsive to the rectified signal and selectively controls the switching device to divert at least a portion of the rectified signal therethrough in response to the rectified signal. A method of supplying power includes coupling a bridge rectifier operatively to an alternating current (ac) signal, the bridge rectifier outputting a rectified signal, coupling a switching device electrically in parallel with the bridge rectifier, and controlling the switching device to divert at least a portion of the rectified signal therethrough in response to the rectified signal.