Feedback control circuit and power management module shortening feedback response time

Patent metadata

Field	Value
Publication number	US-10141840-B2
Application number	US-201614917006-A
Country	US
Kind code	B2
Filing date	Jan 14, 2016
Priority date	Dec 21, 2015
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

Disclosed is a feedback control circuit and a power management module, wherein the feedback control circuit includes a sample analysis circuit, a comparison circuit and a switch control circuit, and the sample analysis circuit samples an output signal of the power management chip, and analyzes a variation trend of the output signal to obtain a first output signal; the comparison circuit compares the first output signal and a reference signal to obtain a second output signal; the switch control circuit comprises a Pulse Width Modulation PWM control circuit and a switch, wherein the PWM control circuit is coupled to the comparison circuit and the switch control circuit, and the switch is coupled to the power management chip, and the switch control signal adjusts a duty ratio of the switch according to the second output signal to adjust a compensation duration of the output signal of the power management chip.

First claim

What is claimed is:

1. A feedback control circuit shortening a feedback response time of a power management chip, wherein the feedback control circuit comprises a sample analysis circuit, a comparison circuit and a switch control circuit, wherein:
the sample analysis circuit is coupled to the power management chip, and employed to sample a power managing output signal of the power management chip, and analyze a variation trend of the power managing output signal to obtain a first output signal;
the comparison circuit is coupled to the sample analysis circuit and the switch control circuit, and employed to compare the first output signal and a reference signal to obtain a second output signal;
the switch control circuit comprises a Pulse Width Modulation PWM control circuit and a switch, wherein the PWM control circuit is coupled to the comparison circuit and the switch, and the switch is coupled to the power management chip, and the switch control circuit is employed to adjust a duty ratio of the switch according to the second output signal to adjust a compensation duration of the power managing output signal of the power management chip to response a variation of the power managing output signal to the switch control circuit in time to reduce a ripple of the output signal the power managing output signal, wherein the differentiating circuit comprises a first operational amplifier, a first capacitor, a first resistor and a second resistor, wherein: an inverting input end of the first operational amplifier is coupled to an output pin of the power management chip sequentially through the first capacitor and first resistor which are coupled in series, and a non-inverting input end of the first operational amplifier is grounded, and an output end of the first operational amplifier is coupled to the comparison circuit, and coupled to the inverting input end of the first operational amplifier through the second resistor.

2. The feedback control circuit according to claim 1 , wherein the sample analysis circuit is a differentiating circuit, and employed to perform differentiating calculation to the power managing output signal to obtain a gradient of the power managing output signal, and the gradient of the output circuit is the first output signal.

3. The feedback control circuit according to claim 1 , wherein a non-inverting input end of the comparison circuit is coupled to an output end of the sample analysis circuit, and an inverting input end of the comparison circuit receives the reference signal, and an output end of the comparison circuit is coupled to the PWM control circuit.

4. The feedback control circuit according to claim 3 , wherein the comparison circuit is employed for:
outputting high voltage level as the first output signal is larger than the reference signal;
outputting low voltage level as the first output signal is smaller than the reference signal.

5. The feedback control circuit according to claim 1 , wherein an input end of the PWM control circuit is coupled to an output end of the comparison circuit; an output end of the PWM control circuit is coupled to a first end of the switch;
a second end of the switch is coupled to the output pin of the power management chip, and a third end of the switch is grounded.

6. The feedback control circuit according to claim 5 , wherein the switch is a metal oxide semiconductor MOS transistor.

7. A power management module shortening a feedback response time of a power management chip, wherein the power management module comprises a power management chip and the feedback control circuit, and the feedback control circuit comprises a sample analysis circuit, a comparison circuit and a switch control circuit, wherein:
the sample analysis circuit is coupled to a power management chip, and employed to sample a power managing output signal of the power management chip, and analyze a variation trend of the power managing output signal to obtain a first output signal;
the comparison circuit is coupled to the sample analysis circuit and the switch control circuit, and employed to compare the first output signal and a reference signal to obtain a second output signal;
the switch control circuit comprises a Pulse Width Modulation PWM control circuit and a switch, wherein the PWM control circuit is coupled to the comparison circuit and the switch, and the switch is coupled to the power management chip, and the switch control circuit is employed to adjust a duty ratio of the switch according to the second output signal to adjust a compensation duration of the power managing output signal of the power management chip to response a variation of the power managing output signal to the switch control circuit in time to reduce a ripple of the output signal the power managing output signal, wherein the differentiating circuit comprises a first operational amplifier, a first capacitor, a first resistor and a second resistor, wherein: an inverting input end of the first operational amplifier is coupled to an output pin of the power management chip sequentially through the first capacitor and first resistor which are coupled in series, and a non-inverting input end of the first operational amplifier is grounded, and an output end of the first operational amplifier is coupled to the comparison circuit, and coupled to the inverting input end of the first operational amplifier through the second resistor.

8. The power management module according to claim 7 , wherein the sample analysis circuit is a differentiating circuit, and employed to perform differentiating calculation to the power managing output signal to obtain a gradient of the output signal, and the gradient of the output circuit is the first output signal.

9. The power management module according to claim 7 , wherein a non-inverting input end of the comparison circuit is coupled to an output end of the sample analysis circuit, and an inverting input end of the comparison circuit receives the reference signal, and an output end of the comparison circuit is coupled to the PWM control circuit.

10. The power management module according to claim 9 , wherein the comparison circuit is employed for:
outputting high voltage level as the first output signal is larger than the reference signal;
outputting low voltage level as the first output signal is smaller than the reference signal.

11. The power management module according to claim 7 , wherein an input end of the PWM control circuit is coupled to an output end of the comparison circuit; an output end of the PWM control circuit is coupled to a first end of the switch;
a second end of the switch is coupled to the output pin of the power management chip, and a third end of the switch is grounded.

12. The power management module according to claim 11 , wherein the switch is a metal oxide semiconductor MOS transistor.

13. The power management module according to claim 7 , wherein the feedback control circuit of the power management chip is integrated inside the power management chip.

14. The power management module according to claim 7 , wherein the power management module further comprises a peripheral control circuit of the power management chip.

Assignees

• Shenzhen China Star Optoelect
• Shenzhen China Star Optoelectronics Co Ltd

Inventors

• Cao Dan
• Zhang Xianming

Classifications

• G05F1/625 Primary

  wherein it is irrelevant whether the variable actually regulated is AC or DC · CPC title

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title