Patent ID: 8575917

Claim:
A power converter providing a DC voltage through a power converter output, the power converter comprising: a first stage comprising an AC to DC power converter comprising a first terminal configured to receive an AC line voltage and a second terminal configured to deliver a first DC voltage wherein the second terminal is coupled to a first intermediate node; a second stage comprising a voltage regulator comprising a third terminal coupled to the first intermediate node and a fourth terminal coupled to a second intermediate node, wherein the second stage is configured to provide a second DC voltage with a limited amount of current to the second intermediate node through the fourth terminal; a switch disposed between the first intermediate node and the second intermediate node; an energy storage device coupled to the first intermediate node and configured to store energy from and deliver energy to the first intermediate node; and a control circuit configured to operate the first stage and the switch, whereby the second intermediate node is coupled to the first intermediate node by the switch when the first stage is in an active state and the first and second stages provide power to the second intermediate node, whereby the second intermediate node is isolated from the first intermediate node by the switch when the first stage is in a standby state and only the second stage provides power to the second intermediate node, wherein the second intermediate node is coupled to the power converter output.