The TPS7A78 improves the overall efficiency and standby power in power supplies for an easy-to-use non-magnetic approach to AC/DC conversion. The TPS7A78 uses an external capacitor to create a current source and actively clamps the rectified voltage. The device then regulates the voltage down to the application-specific operating voltage. The unique architecture of the device allows the standby power to be reduced from several 100s of milliwatts to just a few 10s of milliwatts. The TPS7A78 takes advantage of an innovative switched capacitor stage to reduce the clamped voltage down by approximately 1/4th of the value, which in turn multiplies the current by 4. Thus, the current source capacitor can be much smaller in size, which minimizes standby power, reduces solution size, and can lead to a lower system cost.