Detection method, detection circuit, controller and switching power supply
AssigneeSilergy Semiconductor Technology (Hangzhou) LTD
InventorBo Cai
Life of this patent
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Abstract
Detecting an output voltage of a switching power supply can include: acquiring a first branch current that changes with a first voltage at a first terminal of an inductor of the switching power supply; acquiring a second branch current that changes with a second voltage at a second terminal of the inductor; controlling the first and second branch currents to flow to a same detection terminal; and detecting the output voltage based on a first current flowing through the detection terminal during a first time period, and a second current flowing through the detection terminal during a second time period.
Claims10
A method of detecting an output voltage of a switching power supply, the method comprising:
- a) acquiring a first branch current that changes with a first voltage at a first terminal of an inductor of the switching power supply;
- b) acquiring a second branch current that changes with a second voltage at a second terminal of the inductor;
- c) controlling the first and second branch currents to flow to a same detection terminal, wherein a voltage at the detection terminal is set as a third voltage that is a fixed value, a difference between the first and third voltages is converted to acquire the first branch current, and a difference between the second and third voltages is converted to acquire the second branch current;
- and
- d) detecting the output voltage based on a first current flowing through the detection terminal during a first time period, and a second current flowing through the detection terminal during a second time period, by acquiring a characterization parameter for characterizing the output voltage based on the first and second currents, and comparing the characterization parameter against a reference parameter to detect the output voltage,
- e) wherein the first time period is a time period during which a main power switch in the switching power supply is turned on, and the second time period is a time period during which the main power switch is turned off.
A method of detecting a demagnetization time instant of an inductor of a switching power supply, the method comprising:
- a) acquiring a first branch current that changes with a first voltage at a first terminal of the inductor of the switching power supply;
- b) acquiring a second branch current that changes with a second voltage at a second terminal of the inductor;
- c) controlling the first and second branch currents to flow to a same detection terminal, wherein a voltage at the detection terminal is set as a third voltage that is a fixed value, the first terminal of the inductor is a current input terminal of the inductor, the second terminal of the inductor is a current output terminal of the inductor, a difference between the first and third voltages is converted to acquire the first branch current, and a difference between the second and third voltages is converted to acquire the second branch current;
- and
- d) detecting the demagnetization time instant based on a first current flowing through the detection terminal during a first time period, and a second current flowing through the detection terminal during a second time period, by acquiring a characterization parameter for characterizing an output voltage based on the first and second currents, and comparing the characterization parameter against a reference parameter to detect the output voltage,
- e) wherein the first time period is a time period during which a main power switch in the switching power supply is turned on, and the second time period is a time period during which the main power switch is turned off.
Dependencies are inferred from the claim text.