BATTERY GAS-GAUGE CIRCUIT AND METHOD THEREOF

• US 20100324847A1
• Filed: 01/15/2010
• Published: 12/23/2010
• Est. Priority Date: 06/22/2009
• Status: Active Grant

• Current Assignee: Quanta Computer
• Original Assignee: Quanta Computer
• Inventors: Yen, Wei-Ting
• Granted Patent: US 8,606,533 B2
• Time in Patent Office: Days
• US Class Current: 702/63
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC

Abstract

A battery gas-gauge circuit and method thereof are provided. The battery gas-gauge circuit includes a sensing resistor, a voltage-to-current conversion circuit, a subtractor, a comparator, a logic circuit and a power-management unit. In the voltage-to-current conversion circuit, two conversion circuits thereof obtain two voltage signals according to the two ends of the sensing resistor, respectively, and convert the two voltage signals to two current signals correspondingly. The subtractor generates a current difference signal according to the two current signals. The comparator outputs a comparison signal according to the current difference signal and a current dead-band. The logic circuit outputs a logic signal according to the comparison signal and a predetermined signal. The power-management unit determines battery power according to the logic signal.

Claims

1. A battery gas-gauge circuit, comprising:

a sensing resistor;

a voltage-to-current conversion circuit, comprising;

a first conversion circuit, for obtaining a first voltage signal according to one of the two ends of the sensing resistor, and converting the first voltage signal to a first current signal; and

a second conversion circuit, for obtaining a second voltage signal according to another one of the two ends of the sensing resistor, and converting the second voltage signal to a second current signal;

a subtractor for generating a current difference signal according to the first current signal and the second current signal;

a comparator for outputting a comparison signal according to the current difference signal and a current dead-band;

a logic circuit for outputting a logic signal according to the comparison signal and a predetermined signal; and

a power-management unit for obtaining battery power according to the logic signal.

2. The battery gas-gauge circuit according to claim 1, wherein the predetermined signal is outputted from an enable pin of a charge integrated circuit.

3. The battery gas-gauge circuit according to claim 2, wherein the predetermined signal is previously configured to an enable level.

4. The battery gas-gauge circuit according to claim 2, wherein the predetermined signal is previously configured to an enable level in a power-saving mode.

5. The battery gas-gauge circuit according to claim 4, wherein the power-saving mode is a suspend mode.

6. The battery gas-gauge circuit according to claim 4, wherein the power-saving mode is a power-off mode.

7. The battery gas-gauge circuit according to claim 1, wherein the voltage-to-current conversion circuit, the subtractor, the comparator, and the logic circuit are embodied in an integrated circuit (IC).

8. A method for use in a battery gas-gauge circuit which includes a sensing resistor, the method comprising:

obtaining a first voltage signal according to one of the two ends of the sensing resistor, and converting the first voltage signal to a first current signal; and

obtaining a second voltage signal according to another one of the two ends of the sensing resistor, and converting the second voltage signal to a second current signal;

generating a current difference signal according to the first current signal and the second current signal;

outputting a comparison signal according to the current difference signal and a current dead-band;

outputting a logic signal according to the comparison signal and a predetermined signal; and

obtaining battery power according to the logic signal.

9. The method for use in the battery gas-gauge circuit according to claim 8, wherein the predetermined signal is outputted from an enable pin of a charge integrated circuit.

10. The method for use in the battery gas-gauge circuit according to claim 9, wherein the predetermined signal is previously configured to an enable level.

11. The method for use in the battery gas-gauge circuit according to claim 9, wherein the predetermined signal is previously configured to an enable level in a power-saving mode.

12. The method for use in the battery gas-gauge circuit according to claim 11, wherein the power-saving mode is a suspend mode.

13. The method for use in the battery gas-gauge circuit according to claim 11, wherein the power-saving mode is a power-off mode.