Apparatus for performing multi-loop power control in an electronic device with aid of analog compensation and duty cycle selection, and associated method

Patent metadata

Field	Value
Publication number	US-9831697-B2
Application number	US-201514923403-A
Country	US
Kind code	B2
Filing date	Oct 26, 2015
Priority date	May 15, 2015
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

An apparatus for performing multi-loop power control in an electronic device is provided, where the apparatus may include at least one portion (e.g. a portion or all) of the electronic device. More particularly, the apparatus may include a first amplifier that is positioned in a first feedback loop of the electronic device and coupled to a power control terminal of the electronic device, and a second amplifier that is positioned in a second feedback loop of the electronic device and coupled to the power control terminal. For example, the apparatus may further include a compensation circuit that is coupled to the first amplifier and the second amplifier. In another example, the apparatus may further include a selection control circuit that is coupled to the first amplifier and the second amplifier. An associated method such as an operational method of the above apparatus is also provided.

First claim

What is claimed is:

1. An apparatus for performing multi-loop power control in an electronic device, the apparatus comprising:
a first amplifier, positioned in a first feedback loop of the electronic device and coupled to a power control terminal of the electronic device, arranged for selectively outputting a first error signal toward the power control terminal;
a second amplifier, positioned in a second feedback loop of the electronic device and coupled to the power control terminal, arranged for selectively outputting a second error signal toward the power control terminal; and
a compensation circuit, coupled to the first amplifier and the second amplifier, arranged for detecting the first error signal to generate a compensation signal corresponding to the first error signal and applying the compensation signal to the second error signal, to perform power control of the electronic device.

2. The apparatus of claim 1 , wherein the first amplifier has a first monitoring input terminal for inputting a first monitoring signal and a first reference input terminal for inputting a first reference signal, and the second amplifier has a second monitoring input terminal for inputting a second monitoring signal and a second reference input terminal for inputting a second reference signal.

3. The apparatus of claim 2 , wherein the electronic device utilizes the first feedback loop to monitor the first monitoring signal according to the first reference signal, to perform power control of the electronic device.

4. The apparatus of claim 2 , wherein the electronic device utilizes the second feedback loop to monitor the second monitoring signal according to the second reference signal, to perform power control of the electronic device.

5. The apparatus of claim 1 , wherein the power control terminal receives the first error signal as a feedback of the first feedback loop, to perform power control of the electronic device; and the power control terminal receives the second error signal as a feedback of the second feedback loop, to perform power control of the electronic device.

6. The apparatus of claim 1 , wherein the compensation signal is equivalent to a product of the first error signal and a predetermined factor, wherein the predetermined factor is a non-zero factor.

7. The apparatus of claim 1 , wherein the compensation circuit applies the compensation signal to the second error signal, to reduce influence of the first feedback loop on the second feedback loop during a time period in which the electronic device switches from power control of the second feedback loop to power control of the first feedback loop.

8. The apparatus of claim 1 , wherein the compensation circuit comprises:
a detector, coupled to the first amplifier, arranged for detecting the first error signal to generate a detection signal; and
a compensator, coupled to the detector and the second amplifier, arranged for generating the compensation signal according to the detection signal and applying the compensation signal or a derivative thereof to the second error signal.

9. The apparatus of claim 1 , wherein at least one of the first amplifier and the second amplifier comprises:
an output transconductance amplifier (OTA), arranged for converting a voltage difference into a current error signal.

10. The apparatus of claim 1 , wherein at least one of the first amplifier and the second amplifier comprises:
a current source, arranged for converting a current difference into a current error signal.

11. The apparatus of claim 1 , wherein at least one of the first amplifier and the second amplifier comprises:
an operational amplifier (OPAMP), arranged for converting a voltage difference into a voltage error signal; and
a voltage-to-current converter, arranged for converting the voltage error signal into a current error signal.

12. The apparatus of claim 1 , wherein the power control terminal is a control terminal of a charger within the electronic device; and the electronic device selectively utilizes the first feedback loop to monitor a voltage of a battery charged by the charger in a constant voltage control phase, and selectively utilizes the second feedback loop to monitor a charging current of the battery in a constant current control phase.

13. The apparatus of claim 1 , wherein the power control terminal is a control terminal of a regulating circuit within the electronic device; and the electronic device selectively utilizes the first feedback loop to monitor an output voltage of the regulating circuit, and selectively utilizes the second feedback loop to monitor a current passing through the regulating circuit.

14. The apparatus of claim 1 , wherein the power control terminal is a control terminal of a regulating circuit within the electronic device; and the electronic device selectively utilizes the first feedback loop to monitor an output voltage that the regulating circuit applied to a load, and selectively utilizes the second feedback loop to monitor a current that the regulating circuit draws from a power source of the regulating circuit.

15. An operational method of the apparatus of claim 1 , wherein the operational method comprises:
utilizing the first amplifier to selectively output the first error signal toward the power control terminal;
utilizing the second amplifier to selectively output the second error signal toward the power control terminal; and
applying the compensation signal corresponding to the first error signal to the second error signal, to perform power control of the electronic device.

16. An apparatus for performing multi-loop power control in an electronic device, the apparatus comprising:
a first amplifier, positioned in a first feedback loop of the electronic device, arranged for selectively outputting a first error signal;
a second amplifier, positioned in a second feedback loop of the electronic device, arranged for selectively outputting a second error signal; and
a selection control circuit, coupled to the first amplifier and the second amplifier, arranged for detecting a first pulse width modulation (PWM) signal corresponding to the first error signal and a second PWM signal corresponding to the second error signal to generate at least one detection result, and dynamically selecting one of the first PWM signal and the second PWM signal as a resultant PWM signal according to the at least one detection result, to perform power control of the electronic device.

17. The apparatus of claim. 16 , wherein the selection control circuit monitors a first duty cycle of the first PWM signal and a second duty cycle of the second PWM signal, respectively, to generate the at least one detection result.

18. The apparatus of claim 17 , wherein the at least one detection result comprises statistics data, the statistics data related to at least one of the first duty cycle and the second duty cycle.

19. The apparatus of claim 16 , wherein the selection control circuit comprises:
a plurality of count circuits, arranged for counting the first PWM signal and the second PWM signal to generate a first count result and a second count result, respectively, wherein the at least one detection result comprises the first count result and the second count result; and
a decision circuit, coupled to the plurality of count circuits, arranged for determining, according to the first count result and the second count result, whether one pulse within a pulse of the first PWM signal and a pulse of the second PWM signal appears earlier than another pulse within the pulse of

Assignees

• Mediatek Inc

Inventors

• Kung Nien-Hui

Classifications

• H02J7/90

  Regulation of charging or discharging current or voltage · CPC title

• H02J7/855 Primary

  with circuits adapted for supplying loads from the battery · CPC title

• H02J2207/20

  Charging or discharging characterised by the power electronics converter · CPC title

• H03F2200/351

  Pulse width modulation being used in an amplifying circuit · CPC title

• H03K7/08

  Duration or width modulation {; Duty cycle modulation} · CPC title