Automatic Link Voltage Control Technique for Low Power and Universal Input Applications

This paper proposes an automatic link voltage controller (ALVC) in low power and universal input applications. The ALVC is composed of an auxiliary capacitor and switch, and control circuits. The auxiliary capacitor voltage increases the link voltage in low line. Thus, the link voltage variation can be reduced, which makes higher efficiency of overall circuit. The validity of this proposed circuit is confirmed by the experimental results from 18 V/40 W prototype in universal line.