Patent ID: 8866401
Filing Date: 2014-10-21
Classification: H05B

Abstract:
1. A load control device for controlling the amount of power delivered from a power source to an electrical load, the load control device comprising: a load control circuit adapted to be coupled between the source and the load for controlling the power delivered to the load; a controller operatively coupled to the load control circuit and operable to control the load control circuit to turn the electrical load off; and a multi-stage power supply comprising a first efficient power supply operable to generate a first DC supply voltage output and a second inefficient power supply operable to receive the first DC supply voltage output and to generate a second DC supply voltage output for powering the controller, the first DC supply voltage output having a normal magnitude in a normal mode of operation; wherein the controller is coupled to the multi-stage power supply for controlling the multi-stage power supply to a low-power mode when the electrical load is off, such that the magnitude of the first DC supply voltage output decreases to a decreased magnitude that is less than the normal magnitude and greater than the magnitude of the second DC supply voltage output, and the second inefficient power supply continues to generate the second DC supply voltage output in the low-power mode when the electrical load is off and the magnitude of the first DC supply voltage output has decreased to the decreased magnitude.