Multi-functional battery management module operable in a charging mode and a battery pack mode

• US 6,100,670 A
• Filed: 04/14/1998
• Issued: 08/08/2000
• Est. Priority Date: 04/14/1998
• Status: Expired due to Term

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Conexant Systems Incorporated (Synaptics Incorporated)
• Inventors: Levesque, Chris
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): LUK, LAWRENCE W
• Application Number:
  US09/060,425
• Time in Patent Office: 847 Days
• Field of Search: 320/150, 320/151, 320/152, 320/154, 320/118, 320/127, 320/135, 320/136
• US Class Current: 320/150
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0036 using connection detecting circuits H02J7/0034 takes precedence

Abstract

A control module which controls battery cells is disclosed which can be used in a charging station, a battery pack and in portable devices such as cellular and cordless phones. The control module comprises a first port configured to connect to a battery cell and an input port configured to connect to an external power supply. Further, the control module comprises a detector module configured to generate a detection signal when the external power supply is connected to the input port, a switching module configured to connect to the input port and the first battery port and to select one of said ports, and a selection module configured to connect to the switching module to receive a signal indicative of an electrical characteristic, and to generating status signals indicative of a charging status. Additionally, the control module has a feedback module associated with the selection module to receive the status signals and to generate a drive signal for controlling input from the external power supply. A processor module is associated with the detection module to receive the detection signal, with the selection module to receive the status signals and with the feedback module to receive the drive signal, and generates control signals to control and terminate charging of the battery cells.

Claims

1. A control module for controlling battery cells, the control module being implemented as a single integrated circuit and comprising:

a first port, the first port being configured to connect to a first battery cell;

an input port, the input port being configured to connect to an external power supply;

a detector module, the detector module configured to generate a detection signal when the external power supply is connected to the input port;

a switching module, the switching module configured to connect to the input port and the first battery port and to select one of said ports;

a selection module, the selection module configured to connect to the switching module to receive a signal indicative of an electrical characteristic, and to generate status signals indicative of a charging status;

a feedback module, the feedback module configured to be associated with the selection module to receive the status signals and to generate a drive signal for controlling input from the external power supply; and

a processor module, the processor module associated with the detection module to receive the detection signal, with the selection module to receive the status signals and with the feedback module to receive the drive signal, and to generate control signals to control and terminate charging of the battery cells.

2. The control module of claim 1, further comprising a second port, the second port configured to connect to a second battery cell.

3. The control module of claim 1, further comprising a sensor port for receiving a temperature sensor, the temperature sensor configured to generate a signal indicative of temperature, and to be associated with the processor module receiving the temperature indicative signal.

4. The control module of claim 3, wherein the temperature sensor comprises a resistor, the resistor having a temperature dependent resistance.

5. The control module of claim 3, further comprising an averaging module configured to receive one of the status signals and to generate a signal indicative of average current consumption, the averaging module further configured to be associated with the processor module which receives the signal indicative of the average current consumption.

6. The control module of claim 1, further comprising a discharge module, the discharge module coupled to the processor module and the first battery cell, said discharge module configured to periodically discharge the first battery cell.

7. The control module of claim 6, wherein the periodic discharge occurs at a preset level which is about one percent of a charge current.

8. The control module of claim 7, wherein the discharge module is configured to discharge the first battery cell about once every 3 to 5 seconds.

9. The control module of claim 6, wherein the discharge module comprises a first and second transistor, each transistor being controlled by the processor module to operate between an on-state and an off-state, wherein in the on-state, the first and second transistors are configured to connect the first battery cell to ground.

10. The control module of claim 2, wherein the switching module comprises a first and second transistor, each transistor being controlled by the processor module to operate between an on-state and an off-state, wherein in the on-state, the first transistor is configured to connect the first battery cell to the first port, and the second transistor is configured to connect the second battery to the input port.

11. The control module of claim 10, wherein the switching module further comprises a third transistor, the third transistor being interconnected between the second transistor and a voltage terminal, and being controlled by the processor module.

12. The control module of claim 1, further comprising a register for storing data defining operation modes of the control module.

13. The control module of claim 1, wherein the selection module comprises a selection module and a monitor module, the selection module configured to generate a signal indicative of a charge current and a signal indicative of a voltage value, the monitor module configured to input the status signal to the processor module.

14. The control module of claim 13, wherein the monitor module comprises a multiplexer and an analog-to-digital converter, the multiplexer configured to select under control of the processor module one of the status signals and the analog-to-digital converter configured to convert the selected status signal into a digital signal.

15. The control module of claim 13, wherein the selection module comprises an offset module configured to provide under control of the processor module a positive and a negative offset value selectively.

16. A charging station for a battery cell, comprising:

a power port configured to connect the station to an external power supply;

a battery port configured to connect to at least one battery cell;

a display configured to indicate a charging status of the battery cell; and

a control module configured to control the at least one battery cell, the control module being implemented as a single integrated circuit and comprising;

a first port, the first port being configured to connect to the at least one battery cell;

an input port, the input port being configured to connect to the external power supply;

a detector module, the detector module configured to generate a detection signal when the at least one battery cell is connected to the battery port;

a switching module, the switching module configured to connect the input port and the first battery port;

a selection module, the selection module configured to connect to the switching module to receive a signal indicative of an electrical characteristic, and to generate status signals indicative of a charging status;

a feedback module, the feedback module configured to be associated with the selection module to receive the status signals and to generate a drive signal for controlling input from the external power supply; and

a processor module, the processor module associated with the detection module to receive the detection signal, with the selection module to receive the status signals and with the feedback module to receive the drive signal, and to generate control signals to control and terminate charging of the battery cells.

17. A battery pack comprising a battery cell and a control module for controlling the battery cell, the control module being implemented as a single integrated circuit and comprising:

a first port, the first port being configured to connect to the battery cell;

an input port, the input port being configured to connect to an external power supply;

a detector module, the detector module configured to generate a detection signal when the external power supply is connected to the input port;

a switching module, the switching module configured to connect to the input port and the first battery port and to select one of said ports;

a selection module, the selection module configured to connect to the switching module to receive a signal indicative of an electrical characteristic, and to generate status signals indicative of a charging status;

a feedback module, the feedback module configured to be associated with the selection module to receive the status signals and to generate a drive signal for controlling input from the external power supply; and

a processor module, the processor module configured to be associated with the detection module to receive the detection signal, with the selection module to receive the status signals and with the feedback module to receive the drive signal, and to generate control signals to control and terminate charging of the battery cells.