| 摘要 |
A control circuit and method for controlling the output voltage and/or the output current of a switching power supply. The control circuit includes a transformer with a primary-side and a secondary-side main winding and a primary-side switch for switching on and off the primary current through the primary-side main winding in response to a control signal of the control circuit. The control circuit also includes a primary-side auxiliary winding operable to induce a voltage pulse after the primary-side switch is turned off, and a sample and hold device for sampling and storing a level of the voltage pulse for generating a control variable. |
