Circuit system and method of controlling power management

• US 8,643,375 B2
• Filed: 12/08/2009
• Issued: 02/04/2014
• Est. Priority Date: 12/16/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: ST-Ericcson SA (Telefonaktiebolaget LM Ericsson)
• Inventors: Thorvinger, Jens
• Primary Examiner(s): Assouad, Patrick J
• Assistant Examiner(s): BROWN, LAMARR A
• Application Number:
  US13/139,920
• Publication Number:
  US 20120319694A1
• Time in Patent Office: 1,519 Days
• Field of Search: 324/427, 324/416, 324/433, 713323-324, 713/300, 320/105, 320/107, 320/149
• US Class Current: 324/427
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24

Abstract

A circuit system is disclosed. The system comprises a master circuitry, at least one slave circuitry which has a battery sensor for checking battery status of a power supply battery and a shut down mechanism for controlled shut down upon detection of low battery by the battery sensor, and a battery sensor manipulation circuit controlled by the master circuitry. The battery sensor manipulation circuit is arranged to manipulate sensed battery status for the battery sensor of at least one of the at least one slave circuitry to force the controlled shut down of the at least one of the at least one slave circuitry upon provision of a shut down control signal from the master circuitry. A method of controlling power management of such a circuit system is also disclosed.

Claims

1. A circuit system comprising:

a master circuitry;

at least one slave circuitry which has a battery sensor, having an input, for checking battery status of a power supply battery and a shut down mechanism for controlled shut down upon detection of low battery by the battery sensor; and

a battery sensor manipulation circuit controlled by the master circuitry, the battery sensor manipulation circuit being arranged to manipulate sensed battery status for the battery sensor of at least one of the at least one slave circuitry to force the controlled shut-down of the at least one of the at least one slave circuitry upon provision of a shut-down control signal from the master circuitry.

2. The circuit system of claim 1 wherein the battery sensor manipulation circuit comprises a battery sensor driver circuit comprising:

a first resistor (Rs) connected between the power supply battery and the battery sensor input, wherein the first resistor (Rs) has a resistance that is lower than the impedance of the battery sensor; and

a first current valve (Qs) connected between the battery sensor input and a low voltage point such that the current valve pulls the voltage of the battery sensor low upon provision of a manipulation control signal based on the shut-down control signal from the master circuitry.

3. The circuit system according to claim 1 wherein the battery sensor manipulation circuit comprises battery sensor driver circuit comprising a logical gate controlled by a manipulation control signal based on the shut-down control signal from the master circuitry.

4. The circuit system according to claim 3 wherein the logical gate comprises one of a NOT gate and a level shifter.

5. The circuit system according to claim 2 wherein the battery sensor manipulation circuit further comprises a signal provision circuit comprising:

a second resistor (Rm); and

a second current valve (Qm);

wherein the second resistor (Rm) and second current valve (Qm) are connected in series between the supply battery and a low voltage point such that the second current valve (Qm) is operative to cause the battery sensor driver circuit to output a low voltage upon provision of a high voltage from the master circuitry, and to output a high voltage upon provision of a low voltage from the master circuitry.

6. The circuit system according to claim 5 wherein the battery sensor manipulation circuit further comprises a signal high pass filter (Rf, Cf) interposed between the signal provision circuit and the battery sensor driver circuit.

7. The circuit system according to claim 5, wherein the voltage provided by the master circuitry to the second current valve (Qm) is an internal voltage of the master circuitry.

8. The circuit system according to claim 1 wherein the shut-down control signal from the master circuitry is operative to shut down of all of the at least one slave circuitry upon shut-down of the master circuitry.

9. The circuit system according to claim 1 wherein the shut-down control signal from the master circuitry is operative to selectively shut down of one or more of the at least one slave circuitry.

10. A method of controlling power management of a circuit system comprising a master circuitry, at least one slave circuitry which has a battery sensor for checking battery status of a power supply battery and a shut-down mechanism for controlled shut-down upon detection of low battery by the battery sensor, and a battery sensor manipulation circuit controlled by the master circuitry, the method comprising:

manipulating battery status sensed by the battery sensor of at least one of the at least one slave circuitry to force the controlled shut-down of the at least one of the at least one slave circuitry upon provision of a shut-down control signal from the master circuitry.

11. The method according to claim 10, further comprising controlling shut-down of all of the at least one slave circuitry upon shut-down of the master circuitry by the shut-down control signal from the master circuitry.

12. The method according to claim 10, further comprising selectively controlling shut-down of one or more of the at least one slave circuitry by the shut-down control signal from the master circuitry.