Dimmer control circuit, method and system
AssigneeDelta Electronics, Inc.
InventorsXiaoping Fu, Yugang Bao, Linwei Chen, Xinghua Zhang
Life of this patent
Estimating the term…
Abstract
A dimmer control circuit for controlling a phase cut dimmer includes: a rectifier circuitry, configured to rectify the output voltage of the phase cut dimmer to output a rectified voltage; an input voltage detecting circuitry, configured to output a detected voltage according to the rectified voltage; a processor, configured to output a control signal when the detected voltage meets a preset condition; and a constant current circuitry, configured to output or stop outputting a preset current to the rectifier circuitry in response to the control signal; wherein the preset current has a value greater than a holding current of the phase cut dimmer.
Claims16
A dimmer control circuit for controlling a phase cut dimmer comprising:
- a rectifier circuitry, coupled to an output terminal of the phase cut dimmer and configured to rectify the output voltage of the phase cut dimmer to output a rectified voltage;
- an input voltage detecting circuitry, provided with an input terminal coupled to the rectifier circuitry, and configured to output a detected voltage according to the rectified voltage;
- a processor, provided with an input terminal coupled to an output terminal of the input voltage detecting circuitry, and configured to output a control signal when the detected voltage meets a preset condition;
- and
- a constant current circuitry, provided with a control terminal coupled to an output terminal of the processor and an output terminal coupled to the rectifier circuitry, and configured to output or stop outputting a preset current to the rectifier circuitry in response to the control signal;
- wherein the preset current has a value greater than a holding current of the phase cut dimmer,
- wherein the rectifier circuitry comprises:
- a first diode, provided with an anode coupled to a first terminal of the output terminal of the phase cut dimmer, and a cathode coupled to a first node;
- and
- a second diode, provided with an anode coupled to a second terminal of the output terminal of the phase cut dimmer, and a cathode coupled to the first node, and
- wherein the constant current circuitry comprises:
- a first switching device provided with a first terminal, a second terminal, and a control terminal, the first terminal being coupled to the first node, the second terminal being coupled to a second node, and the control terminal being coupled to a third node;
- a third resistor, provided with one terminal coupled to the second node, and another terminal grounded;
- a second switching device provided with a first terminal, a second terminal, and a control terminal, the first terminal being coupled to the third node, the second terminal being grounded, and the control terminal being coupled to the output terminal of the processor;
- a fourth resistor, provided with one terminal coupled to a DC voltage source, and another terminal coupled to the third node;
- and
- a zener diode provided with a cathode coupled to the third node and an anode grounded.
Dependencies are inferred from the claim text.