AC/DC conversion bypass power delivery

摘要

An LED lamp control circuit directly drives an array of series or parallel connected LEDs with current directly derived from the rectified AC voltage. Electrolytic capacitors are eliminated, and the circuit is independent of forward bias voltage of the LEDs, which vary by lot and manufacturer. For example, in an embodiment, an light-emitting diode (LED) lamp control circuit includes a transistor, an LED load comprising one or more LEDs, a power storage device configured to provide power to the LED load, and a controller circuit configured to control the transistor to charge and discharge the power storage device based on sensed voltages of a first node and a second node and a current passing through the power storage device. The power storage device and the LED load are arranged in parallel between the first node and the second node. A voltage source is coupled to the first node and a first terminal of the transistor is coupled to the second node. A second terminal of the transistor is coupled to ground.

主权项

1. A light-emitting diode (LED) lamp control circuit, comprising:
a transistor; an LED load comprising one or more LEDs; a power storage device configured to provide power to the LED load, wherein the power storage device and the LED load are arranged in parallel between a first node and a second node, wherein a voltage source is coupled to the first node and a first terminal of the transistor is coupled to the second node, and wherein a second terminal of the transistor is coupled to ground; a controller circuit configured to control the transistor to charge and discharge the power storage device based on sensed voltages of the first and second nodes and a current passing through the power storage device.