Method and a system for producing a power supply voltage for controlling an electronic switch

摘要

A direct current supply voltage for controlling an electronic switch, for example a triac, is obtained from a residual voltage at the terminals of the switch when it is conducting. The electrical energy needed to produce an auxiliary power supply voltage is taken from the terminals of the electronic switch while it is conducting. The residual voltage is rectified and stepped up, for example using a regulated switch-mode power supply circuit as a rectifier/voltage step-up system.