Dimming signal generation circuit, dimming signal generation method and LED driver
AssigneeSilergy Semiconductor Technology (Hangzhou) LTD
InventorsLongqi Wang, Jianxin Wang
Life of this patent
Estimating the term…
Abstract
A dimming signal generation circuit configured for an LED driver can include: a voltage-type dimmer configured to generate a dimming voltage; a dimming control circuit comprising a transformer and a power switch coupled in series between a first voltage and ground; where a secondary side of the transformer is coupled to the voltage-type dimmer is configured to receive the dimming voltage; where a primary side of the transformer is configured to receive the first voltage; and where a dimming reference signal is generated at the primary side of the transformer in accordance with the dimming voltage.
Claims20
A dimming signal generation circuit configured for a light-emitting diode (LED) driver, the dimming signal generation circuit comprising:
- a voltage-type dimmer configured to generate a dimming voltage;
- a dimming control circuit comprising a transformer and a power switch coupled in series between a first voltage and ground;
- wherein a secondary side of the transformer is coupled to the voltage-type dimmer is configured to receive the dimming voltage;
- wherein a primary side of the transformer is configured to receive the first voltage;
- wherein a dimming reference signal is generated at the primary side of the transformer in accordance with the dimming voltage;
- and
- wherein a non-dotted terminal of a primary winding of the transformer is configured to receive the first voltage, a dotted terminal of the primary winding of the transformer is coupled to the power switch, and a dotted terminal of a secondary winding of the transformer is coupled to a high potential output terminal of the voltage-type dimmer.
A dimming signal generation method of controlling a dimming signal generation circuit, wherein the dimming signal generation circuit comprises a voltage-type dimmer and a dimming control circuit having a transformer and a power switch coupled in series between a first voltage and ground, the method comprising:
- generating a dimming voltage by the voltage-type dimmer in accordance with a brightness of a light-emitting diode (LED) load;
- receiving the dimming voltage by a secondary side of the transformer;
- receiving the first voltage by a primary side of the transformer;
- generating a dimming reference signal in accordance with the dimming voltage at the primary side of the transformer in the dimming control circuit;
- and
- generating a detection signal by sampling a voltage at a common node between the primary winding of the transformer and the power switch, wherein the first voltage is constant.
A dimming signal generation method of controlling a dimming signal generation circuit, wherein the dimming signal generation circuit comprises a voltage-type dimmer and a dimming control circuit having a transformer and a power switch coupled in series between a first voltage and ground, the method comprising:
- generating a dimming voltage by the voltage-type dimmer in accordance with a brightness of a light-emitting diode (LED) load;
- receiving the dimming voltage by a secondary side of the transformer;
- receiving the first voltage by a primary side of the transformer;
- generating a dimming reference signal in accordance with the dimming voltage at the primary side of the transformer in the dimming control circuit;
- and
- generating a detection signal in accordance with a difference between the first voltage and a voltage at the common node between the primary winding of the transformer and the power switch.
Dependencies are inferred from the claim text.