Control method and control circuit for an AC-DC power supply
AssigneeSilergy Semiconductor Technology (Hangzhou) LTD
InventorsLongqi Wang, Jianxin Wang
Life of this patent
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Abstract
A control circuit for controlling an AC-DC power supply, can include: a pulse-width modulation (PWM) signal generating circuit configured to generate a PWM signal in accordance with a reference voltage and a current sampling signal representing an inductor current flowing through an inductor of the AC-DC power supply, and to control a power stage circuit of the AC-DC power supply in accordance with the PWM signal; and a reference voltage generating circuit configured to generate the reference voltage based on an input voltage of the AC-DC power supply.
Claims18
A control circuit for controlling an AC-DC power supply, the control circuit comprising:
- a) a pulse-width modulation (PWM) signal generating circuit configured to generate a PWM signal in accordance with a reference voltage and a current sampling signal representing an inductor current flowing through an inductor of the AC-DC power supply, and to control a power stage circuit of the AC-DC power supply in accordance with the PWM signal;
- and
- b) a reference voltage generating circuit configured to generate the reference voltage based on an input voltage of the AC-DC power supply, wherein a corresponding relationship between the reference voltage and the input voltage is determined in accordance with a topology of the power stage circuit, such that an envelope of peak values of the inductor current varies sinusoidally with the input voltage,
- c) wherein the reference voltage is proportional to a product of the input voltage, a sum of the input voltage and an output voltage of the AC-DC power supply, and a compensation signal, or the reference voltage is proportional to a product of a square of the input voltage and the compensation signal.
A method of controlling an AC-DC power supply, the method comprising:
- a) generating a pulse-width modulation (PWM) signal in accordance with a reference voltage and a current sampling signal representing an inductor current flowing through an inductor of the AC-DC power supply;
- b) controlling a power stage circuit of the AC-DC power supply in accordance with the PWM signal;
- and
- c) generating the reference voltage based on an input voltage of the AC-DC power supply, wherein a corresponding relationship between the reference voltage and the input voltage is determined in accordance with a topology of the power stage circuit, such that an envelope of peak values of the inductor current varies sinusoidally with the input voltage,
- d) wherein the reference voltage is proportional to a product of the input voltage, a sum of the input voltage and an output voltage of the AC-DC power supply, and a compensation signal, or the reference voltage is proportional to a product of a square of the input voltage and the compensation signal.
Dependencies are inferred from the claim text.