Battery-charger device with improved stability

• US 7,692,406 B2
• Filed: 06/16/2004
• Issued: 04/06/2010
• Est. Priority Date: 06/18/2003
• Status: Active Grant

• Current Assignee: Microelectronic Innovations LLC
• Original Assignee: STMicroelectronics Design and Application GmbH (STMicroelectronics NV), STMicroelectronics SA (STMicroelectronics NV), STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Bernard, Christopher, Milazzo, Patrizia, Mercadante, Giacomo, Chesnau, David
• Primary Examiner(s): Tso; Edward
• Assistant Examiner(s): Fantu; Yalkew
• Application Number:
  US10/869,512
• Publication Number:
  US 20050040791A1
• Time in Patent Office: 2,120 Days
• Field of Search: 320/135, 320/163, 320/162, 320/107, 320/132, 323/274
• US Class Current: 320/135
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters

Abstract

A circuit is provided for controlling a battery-charger device with a closed-loop architecture. The circuit includes sensing means for sensing an operative quantity of the device, control means, and driving means. The control means alternately controls the sensing means to track the operative quantity during a tracking phase and to hold the operative quantity during a holding phase. The driving means provides a regulation signal that regulates the operative quantity based on a comparison between the operative quantity sensed by the sensing means and a reference value. The control means causes the driving means to hold the regulation signal during at least part of each of the holding phases. Also provided is a method of controlling a battery-charger device with a closed-loop architecture.

Claims

1. A circuit for controlling a battery-charger device with a closed-loop architecture, the circuit comprising:

sensing means for sensing an operative quantity of the device and comparing the operative quantity that is sensed with a reference value;

control means for controlling the sensing means such that the sensing means alternately tracks the operative quantity during a tracking phase and holds the operative quantity during a holding phase; and

driving means for generating a regulation signal so as to regulate the operative quantity based on a result of the comparison by the sensing means,

wherein the control means controls the driving means such that the driving means holds the regulation signal during at least part of each of the holding phases during which the sensing means holds the operative quantity.

2. The circuit according to claim 1, wherein the control means controls the driving means such that the driving means holds the regulation signal during all of each of the holding phases.

3. The circuit according to claim 1, wherein the control means controls the driving means such that the driving means holds the regulation signal during all of each of the holding phases and during a starting part of each of the tracking phases.

4. The circuit according to claim 1, wherein the control means provides a clock signal to the driving means, the driving means holding the regulation signal according to a duty-cycle of the clock signal.

5. The circuit according to claim 4,

wherein the sensing means provides an error signal indicative of the result of the comparison between the operative quantity that is sensed and the reference value, and

the driving means includes an amplifier for generating the regulation signal by amplifying the error signal, the amplifier including an input stage for receiving the error signal, an output stage for providing the regulation signal, capacitive means connected in feedback to the output stage, and means responsive to the clock signal for disconnecting the output stage from the input stage.

6. The circuit according to claim 1, wherein the operative quantity is a charging current for charging a battery.

20. The circuit according to claim 1, further comprising reference voltage generating means for generating a reference voltage, the reference voltage being the reference value.

7. A battery-charger device with a closed-loop architecture, said battery-charger device comprising:

a sensing circuit for sensing an operative quantity of the device and comparing the operative quantity that is sensed with a reference value;

a control circuit for controlling the sensing circuit such that the sensing circuit alternately tracks the operative quantity during a tracking phase and holds the operative quantity during a holding phase;

a regulation circuit for regulating the operative quantity in response to a regulation signal; and

a driving circuit for generating the regulation signal and providing the regulation signal to the regulation circuit so as to regulate the operative quantity based on a result of the comparison by the sensing circuit;

wherein the control circuit controls the driving circuit such that the driving circuit holds the regulation signal during at least part of each of the holding phases during which the sensing circuit holds the operative quantity.

8. The battery-charger device according to claim 7, wherein the control circuit controls the driving circuit such that the driving circuit holds the regulation signal during all of each of the holding phases.

9. The battery-charger device according to claim 7, wherein the control circuit controls the driving circuit such that the driving circuit holds the regulation signal during all of each of the holding phases and during a starting part of each of the tracking phases.

10. The battery-charger device according to claim 7, wherein the control circuit provides a clock signal to the driving circuit, the driving circuit holding the regulation signal according to a duty-cycle of the clock signal.

11. The battery-charger device according to claim 10,

wherein the sensing circuit provides an error signal indicative of the result of the comparison between the operative quantity that is sensed and the reference value, and

the driving circuit includes an amplifier for generating the regulation signal by amplifying the error signal, the amplifier including an input stage for receiving the error signal, an output stage for providing the regulation signal, capacitive means connected in feedback to the output stage, and means responsive to the clock signal for disconnecting the output stage from the input stage.

12. The battery-charger device according to claim 7, wherein the operative quantity is a charging current for charging a battery.

13. A portable electronic system comprising:

a functional unit;

a battery coupled to the functional unit for supplying power to the functional unit; and

the battery-charger device according to claim 7 for charging the battery.

14. A method of controlling a battery-charger device with a closed-loop architecture, said method comprising:

sensing an operative quantity of the device so as to alternately track the operative quantity during a tracking phase and hold the operative quantity during a holding phase;

comparing the operative quantity that is sensed with a reference value;

generating a regulation signal so as to regulate the operative quantity based on a result of the comparison between the operative quantity that is sensed and the reference value; and

holding the regulation signal during at least part of each of the holding phases during which the operative quantity is held.

15. The method according to claim 14, wherein in the holding step, the regulation signal is held during all of each of the holding phases.

16. The method according to claim 14, wherein in the holding step, the regulation signal is held during all of each of the holding phases and a starting part of each of the tracking phases.

17. The method according to claim 14,

wherein the comparing step includes generating an error signal indicative of the result of the comparison;

and

the generating step includes generating the regulation signal by amplifying the error signal.

18. The method according to claim 14, further comprising the step of regulating the operative quantity in response to the regulation signal.

19. The method according to claim 14, wherein the operative quantity is a charging current for charging a battery.