Operating method for switch-mode power supply with flyback converter e.g. for television set with standby mode, using storage capacitor to cause early start of next switch-on phase

摘要

In standby mode, an electronic switch connected to the primary side of a transformer is driven in a burst cycle during a switch-on phase that is shorter than the switch-off phase. A secondary-side output voltage (U2) from the transformer is monitored, and if the output voltage falls below a threshold, a storage capacitor charged in a previous burst cycle is used to cause an early start of the next switch-on phase. An Independent claim is also included for a switch-mode power supply.