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US 12,563,651 B2Granted
Methods and apparatus to supply power to LED circuitry
AssigneeTexas Instruments Incorporated
InventorsRaja Reddy Patukuri, Anand Hariraj Udupa, Aravind Miriyala, Sandeep Oswal, Rajat Agarwal
Life of this patent
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Abstract
An example apparatus includes: driver circuitry having a first terminal and a second terminal; and voltage control circuitry having a first terminal and a second terminal, the first terminal of the voltage control circuitry coupled to the first terminal of the driver circuitry, the second terminal of the voltage control circuitry coupled to the second terminal of the driver circuitry, the voltage control circuitry configured to supply an LED supply voltage.
Claims20
A system comprising:
- a first light emitting diode (LED) having a first terminal and a second terminal;
- a second LED having a first terminal and a second terminal, the first terminal of the second LED coupled to the first terminal of the first LED;
- driver circuitry having a first terminal and a second terminal, the first terminal of the driver circuitry coupled to the second terminal of the first LED, the second terminal of the driver circuitry coupled to the second terminal of the second LED;
- a first switch having a first terminal and a second terminal, the first terminal of the first switch coupled to the second terminal of the first LED and the first terminal of the driver circuitry;
- a second switch having a first terminal and a second terminal, the first terminal of the second switch coupled to the second terminal of the second LED and the second terminal of the driver circuitry;
- sense control circuitry having a first terminal, a second terminal, and a third terminal, the first terminal of the sense control circuitry coupled to the second terminal of the first switch, the second terminal of the sense control circuitry coupled to the second terminal of the second switch, the sense control circuitry configured to determine a headroom voltage of the driver circuitry for the first and second LEDs;
- and
- power converter having a control terminal and an output, the control terminal of the power converter coupled to the third terminal of the sense control circuitry, the output of the power converter coupled to the first terminal of the first LED and the first terminal of the second LED;
- wherein the sense control circuitry further includes:
- an analog to digital converter (ADC) having a first terminal and a second terminal, the first terminal of the ADC configured to be coupled to the second terminal of the first switch and the second terminal of the second switch;
- and
- comparison circuitry having a first terminal, a second terminal, and a third terminal, the first terminal of the comparison circuitry coupled to the second terminal of the ADC, the second terminal of the comparison circuitry configured to be coupled to the third terminal of the comparison circuitry.
9 more elements
A system comprising:
- a first light emitting diode (LED) having a first terminal and a second terminal;
- a second LED having a first terminal and a second terminal, the first terminal of the second LED coupled to the first terminal of the first LED;
- driver circuitry having a first terminal and a second terminal, the first terminal of the driver circuitry coupled to the second terminal of the first LED, the second terminal of the driver circuitry coupled to the second terminal of the second LED;
- a first switch having a first terminal and a second terminal, the first terminal of the first switch coupled to the second terminal of the first LED and the first terminal of the driver circuitry;
- a second switch having a first terminal and a second terminal, the first terminal of the second switch coupled to the second terminal of the second LED and the second terminal of the driver circuitry;
- sense control circuitry having a first terminal, a second terminal, and a third terminal, the first terminal of the sense control circuitry coupled to the second terminal of the first switch, the second terminal of the sense control circuitry coupled to the second terminal of the second switch, the sense control circuitry configured to determine a headroom voltage of the driver circuitry for the first and second LEDs;
- and
- power converter having a control terminal and an output, the control terminal of the power converter coupled to the third terminal of the sense control circuitry, the output of the power converter coupled to the first terminal of the first LED and the first terminal of the second LED;
- wherein the driver circuitry includes:
- a third switch having a first terminal and a second terminal, the first terminal of the third switch coupled to the second terminal of the first LED;
- and
- a fourth switch having a first terminal and a second terminal, the first terminal of the fourth switch coupled to the second terminal of the second LED, the second terminal of the fourth switch coupled to the second terminal of the third switch;
- and
- wherein the first switch, the second switch, the third switch, and the fourth switch further have a control terminal, further comprising switch control circuitry having a first terminal and a second terminal, the first terminal of the switch control circuitry coupled to the control terminal of the first switch and the third switch, the second terminal of the switch control circuitry coupled to the control terminal of the second switch and the fourth switch.
11 more elements
An apparatus comprising:
- driver circuitry having a first terminal and a second terminal;
- and
- voltage control circuitry having a first terminal and a second terminal, the first terminal of the voltage control circuitry coupled to the first terminal of the driver circuitry, the second terminal of the voltage control circuitry coupled to the second terminal of the driver circuitry, the voltage control circuitry configured to supply a supply voltage;
- wherein the voltage control circuitry comprises:
- a first switch having a terminal coupled to the first terminal of the driver circuitry;
- a second switch having a terminal coupled to the second terminal of the driver circuitry;
- and
- sense control circuitry including:
- an analog to digital converter (ADC) having a first terminal and a second terminal, the first terminal of the ADC configured to be coupled to the second terminal of the first switch and the second terminal of the second switch;
- and
- comparison circuitry having a first terminal, a second terminal, and a third terminal, the first terminal of the comparison circuitry coupled to the second terminal of the ADC, the second terminal of the comparison circuitry configured to be coupled to the third terminal of the comparison circuitry.
8 more elements
A device comprising:
- driver circuitry having a first terminal and a second terminal, the driver circuitry to source a current from one of the first terminal or the second terminal;
- and
- voltage control circuitry configured to:
- determine a first headroom voltage corresponding to a current to flow through the first terminal of the driver circuitry;
- determine a second headroom voltage corresponding to a current flowing through the second terminal of the driver circuitry;
- determine a modified LED supply voltage based on the first headroom voltage and the second headroom voltage;
- and
- determine the first headroom voltage based on a voltage difference across the driver circuitry when a current is flowing through one of the terminals of the driver circuitry.
5 more elements
A device comprising:
- driver circuitry having a first terminal and a second terminal, the driver circuitry to source a current from one of the first terminal or the second terminal;
- and
- voltage control circuitry configured to:
- determine a first headroom voltage corresponding to a current to flow through the first terminal of the driver circuitry;
- determine a second headroom voltage corresponding to a current flowing through the second terminal of the driver circuitry;
- determine a modified LED supply voltage based on the first headroom voltage and the second headroom voltage;
- and
- switch control circuitry configured to:
- control a first switch and a second switch of the driver circuitry, a current to flow through a specific one of the first or the second terminal of the driver circuitry responsive to the switch control circuitry;
- and
- control a third switch and a fourth switch of the voltage control circuitry to determine the first headroom voltage or the second headroom voltage.
8 more elements
Dependencies are inferred from the claim text.