Patent ID: 9553520
Date: 2017-01-24
CPC Classifications: H02M,H03K,Y02B

Claim:
1. A switching power source, comprising: a filtering and rectifying module, connected with an AC power source and configured to filter an alternating current outputted from the AC power source to obtain a filtered alternating current and to rectify the filtered alternating current into a direct current; a control module, connected with the filtering and rectifying module and configured to obtain an amplitude of the alternating current from the direct current, to adjust a frequency of a control signal output according to the amplitude of the alternating current, wherein the control module decreases the frequency of the control signal continuously or intermittently when the amplitude of the alternating current increases, and to output the control signal; and a primary constant current circuit, connected with the control module and the filtering and rectifying module respectively, and configured to receive the control signal and to output a constant current according to the control signal.