US 2019/0059135 A1 · DRIVING CIRCUIT USING BUCK CONVERTER CAPABLE OF GENERATING SUFFICIENT VOLTAGE TO POWER A LED CIRCUIT AND ASSOCIATED AUXILIARY CIRCUITRY IN A NORMAL MODE OF OPERATION, AND INSUFFICIENT TO POWER THE LED CIRCUIT BUT SUFFICIENT TO POWER THE ASSOCIATED AUXILIARY CIRCUITRY IN AN OFF MODE OF OPERATION

Abstract

A circuit includes a voltage converter converting source voltage to supply voltage at a first node as a function of a feedback voltage at a feedback node. A first output path is coupled between first and second node nodes. Feedback circuitry couples the second node to the feedback node when a voltage at the second node exceeds a first overvoltage, in a first mode of operation. The feedback circuitry couples the second node to the feedback node when the voltage at the second node exceeds a second overvoltage less than the first overvoltage, in a second mode of operation. Impedance circuitry is coupled between the first node and a third node and generates an auxiliary supply voltage and an auxiliary ground voltage when the circuit is in both the first and second modes, the auxiliary supply voltage being less than the supply voltage in both the first and second modes.

Claims30

Dependent claims

A circuit, comprising:

voltage converter configured to convert a source voltage to a supply voltage at a first node as a function of a feedback voltage at a feedback node;
a first output path coupled between the first node and a second node;
feedback circuitry configured to
couple the second node to the feedback node when a voltage at the second node exceeds a first overvoltage, when the circuit is in a first mode of operation;
couple the second node to the feedback node when the voltage at the second node exceeds a second overvoltage less than the first overvoltage, when the circuit is in a second mode of operation;
impedance circuitry coupled between the first node and a third node and configured to generate an auxiliary supply voltage and an auxiliary ground voltage when the circuit is in both the first and second modes of operation, the auxiliary supply voltage being less than the supply voltage in both the first and second modes of operation.

3 more elements

A method, comprising:

converting an input voltage to an output voltage using a switching voltage converter circuit, in response to a feedback voltage;
in a normal mode of operation,
providing the feedback voltage to the switching voltage converter circuit at a voltage level sufficient to stop switching of the switching voltage converter circuit if the output voltage exceeds a first overvoltage;
providing the feedback voltage to the switching voltage converter circuit at a voltage level insufficient to stop switching of the switching voltage converter circuit if the output voltage is less than the first overvoltage;
powering a LED circuit and an auxiliary circuit using the output voltage, wherein the output voltage is sufficient to power the LED circuit and the auxiliary circuit;
in an off mode of operation,
providing the feedback voltage to the switching voltage converter circuit at a voltage level sufficient to stop switching of the switching voltage converter circuit if the output voltage exceeds a second overvoltage less than the first overvoltage;
providing the feedback voltage to the switching voltage converter circuit at a voltage level insufficient to stop switching of the switching voltage converter circuit if the output voltage is less than the second overvoltage;
powering an auxiliary circuit using the output voltage, wherein the output voltage is sufficient to power the auxiliary circuit and insufficient to power the LED circuit.

6 more elements

A circuit, comprising:

voltage converter configured to convert a source voltage to a supply voltage at a first node as a function of a feedback voltage at a feedback node;
a first output path coupled between the first node and a second node;
feedback circuitry configured to
couple the second node to the feedback node when a voltage at the second node exceeds an overvoltage, when the circuit is in a first mode of operation;
impedance circuitry coupled between the first node and a third node and configured to generate an auxiliary supply voltage and an auxiliary ground voltage, the auxiliary supply voltage being less than the supply voltage;
a LED chain coupled to the third node, being turned on by the supply voltage when the circuit is in a second mode of operation, and not being turned on by the supply voltage when the circuit is in the first mode of operation;
an auxiliary power supply coupled to the auxiliary supply voltage and auxiliary ground voltage;
a microcontroller powered by the auxiliary power supply and configured to generate a LED dimmer control signal to be coupled to the feedback node;
and
a wireless module powered by the auxiliary power supply and configured to relay user commands to the microcontroller.

7 more elements

Dependencies are inferred from the claim text.

Driving circuit using buck converter capable of generating sufficient voltage to power a led circuit and associated auxiliary circuitry in a normal mode of operation, and insufficient to power the led circuit but sufficient to power the associated auxiliary circuitry in an off mode of operation

Life of this patent

Driving circuit using buck converter capable of generating sufficient voltage to power a led circuit and associated auxiliary circuitry in a normal mode of operation, and insufficient to power the led circuit but sufficient to power the associated auxiliary circuitry in an off mode of operation

Life of this patent

Abstract

Claims30