High frequency clocked switch-mode power supply based on fly-back converter principal, has radio-interference suppression device of series circuit of two capacitors arranged between

摘要

Switching power supplies require suppression of radio frequency interference and can be designed by connecting the core to the primary side earth or a radio frequency interference capacitor can be arranged between the primary and secondary side but this increases circuit costs, particularly when the capacitor requires a high electric strength. By electrically connecting the transformer core to each capacitor (C3,C4), of which one is connected to the DC-voltage potential on the primary side and the other on the secondary side, a particularly good interference suppressing action is obtained.