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US 9,866,117 B2Granted
Power supply with adaptive-controlled output voltage
AssigneeCree, Inc.
InventorsYuequan Hu, Daniel Pope
Life of this patent
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Abstract
A power supply circuit includes a pre-regulator configured to receive an input voltage and to generate an output voltage, and a switching current regulator coupled to an output of the pre-regulator and configured to regulate a level of current supplied to an output load. The switching current regulator is controlled by a switching signal having a duty cycle. The circuit further includes a controller that generates the switching signal. The controller monitors the duty cycle of the switching signal and controls a level of the output voltage generated by the pre-regulator by providing a control signal in response to the duty cycle of the switching signal.
Claims12
A power supply circuit, comprising:
- a voltage regulator configured to receive an input voltage and to generate an output voltage;
- a switching current regulator coupled to an output of the voltage regulator and configured to regulate a level of current supplied to an output load, wherein the switching current regulator is controlled by a switching signal having a duty cycle;
- and
- a controller configured to generate the switching signal;
- wherein the controller is configured to monitor the duty cycle of the switching signal and to control a level of the output voltage generated by the voltage regulator in response to a comparison between a threshold value and the duty cycle of the switching signal;
- wherein the voltage regulator is configured to receive a control signal and set the level of the output voltage in response to the control signal and the controller is configured to supply the control signal to the voltage regulator and to control the level of the output voltage by changing a level of the control signal;
- and
- wherein the controller is configured to reduce the level of the output voltage generated by the voltage regulator in response to the comparison, wherein the comparison indicates that the duty cycle of the switching signal is below the threshold value;
- wherein the threshold value comprises a first threshold value, and wherein the controller is further configured:
- to compare the duty cycle of the switching signal to a second threshold value that is higher than the first threshold value;
- and
- to stop reducing the level of the output voltage in response to determining that the duty cycle of the switching signal is greater than the second threshold value, wherein the first threshold value and the second threshold value provide hysteresis in the control of the output voltage level.
9 more elements
A power supply circuit, comprising:
- a voltage regulator configured to receive an input voltage and to generate an output voltage;
- a plurality of switching current regulators coupled to an output of the voltage regulator and configured to regulate levels of current supplied to respective output loads, wherein the switching current regulators are controlled by switching signals having respective duty cycles;
- and
- a controller configured to generate the switching signals;
- wherein the controller is configured to monitor the duty cycles of the switching signals and to control a level of the output voltage generated by the voltage regulator in response to performing a comparison between a highest one of the duty cycles of the switching signals and a threshold value;
- wherein the voltage regulator is configured to receive a control signal and set the level of the output voltage in response to the control signal and the controller is configured to supply the control signal to the voltage regulator and to control the level of the output voltage by changing a level of the control signal;
- and
- wherein the controller is configured to reduce the level of the output voltage generated by the voltage regulator in response to the comparison, wherein the comparison indicates that the highest one of the duty cycles of the switching signals is below the threshold value;
- wherein the threshold value comprises a first threshold value, and wherein the controller is further configured:
- to compare the duty cycles of the switching signals to a second threshold value that is higher than the first threshold value;
- and
- to stop reducing the level of the output voltage in response to determining that the highest one of the duty cycles of the switching signals is greater than the second threshold value, wherein the first threshold value and the second threshold value provide hysteresis in the control of the output voltage level.
9 more elements
A method of operating a power supply circuit including a voltage regulator that receives an input voltage and generates an output voltage and a switching current regulator that regulates a level of current supplied to an output load and that is controlled by a switching signal having a duty cycle, the method comprising:
- monitoring the duty cycle of the switching signal;
- performing a comparison between the duty cycle of the switching signal and a threshold value;
- and
- controlling a level of the output voltage generated by the voltage regulator in response to the comparison;
- wherein the voltage regulator is configured to receive a control signal and to set the level of the output voltage in response to the control signal, the method further comprising:
- supplying the control signal to the voltage regulator;
- controlling the level of the output voltage by changing a level of the control signal;
- and
- changing the level of the control signal to reduce the level of the output voltage generated by the voltage regulator in response to determining that the duty cycle of the switching signal is below the threshold value;
- wherein the threshold value comprises a first threshold value, the method further comprising:
- comparing the duty cycle of the switching signal to a second threshold value that is higher than the first threshold value;
- and
- controlling the level of the control signal to stop reducing the level of the output voltage in response to determining that the duty cycle of the switching signal is greater than the second threshold value, wherein the first threshold value and the second threshold value provide hysteresis in the control of the output voltage level.
10 more elements
Dependencies are inferred from the claim text.