Battery management and protection system using a module in a sleepwalking mode to monitor operational characteristics of a battery

• US 8,943,335 B2
• Filed: 12/22/2010
• Issued: 01/27/2015
• Est. Priority Date: 12/22/2010
• Status: Active Grant

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Holsen, Eivind, Onsum, Andreas, Svendsli, Odd Jostein, Aas, Arne
• Primary Examiner(s): Lee, Thomas
• Assistant Examiner(s): CASSITY, ROBERT A
• Application Number:
  US12/976,884
• Publication Number:
  US 20120162828A1
• Time in Patent Office: 1,497 Days
• Field of Search: 713/300, 320/132, 320/134
• US Class Current: 713/300
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H02H 3/08 responsive to excess current responsive to abnormal temperature caused by excess current H02H5/04
• CPC Class Codes: H02H 3/202 for dc systems
• CPC Class Codes: H02H 5/04 responsive to abnormal temperature specially adapted for electric machines H02H7/0852
• CPC Class Codes: H02H 5/041 additionally responsive to excess current H02H5/048 takes precedence
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery management and protection system can include various features to improve safety-critical and other functions. Among the features that can be included in some implementations are automatic loading of safety or other parameters during start-up of the system; a centralized timekeeper and an event system that can trigger actions in the system independently of a central processing unit; use of the same modules for both automatically-controlled safety-related measurements and firmware-controlled measurements; enhanced diagnostic features, and a sleepwalking feature that allows certain modules in the system to continue to perform various functions even when the module or the system is in a low-power sleep mode.

Claims

1. A battery management and protection system having an active mode and one or more low-power sleep modes, the system comprising:

a central processing unit that is inactive while the system is in the one or more low-power sleep modes;

a module, other than the central processing unit, to receive signals indicative of an operational characteristic of a battery and to determine whether the characteristic is within a predetermined range;

a timekeeper that includes a prescaler to generate a plurality of different divided signals from a clock signal, each of the divided signals having a respective frequency, the plurality of divided signals representing events; and

a dedicated routing network to pass the events directly from the timekeeper to the module,

wherein, when the system is in the one or more low-power sleep modes, the module operates in a sleepwalking mode in which the module is operable to select and respond to a specified one of the events from the timekeeper, independently of the central processing unit, even if the event from the timekeeper is sent while the module is sleeping, wherein the specified one of the events has a predetermined frequency that the module is programmed to select, and wherein the module is operable to return to sleep after performing a specified action triggered by the specified event received from the timekeeper.

3. The system of claim 1 wherein the module is operable to measure at least one of voltage or temperature of the battery and compare the measured voltage or temperature to a specified level.

4. The system of claim 1 wherein the module is operable to measure current for the battery and determine whether the measured current is within a specified range.

5. The system of claim 1 wherein the module is operable to sample voltages for the battery and compare the sampled voltages to a specified level.

9. The system of claim 1 wherein the module has a dedicated input/output register storing information auto-loaded to the register during system start-up, wherein the module is programmed to select the specified one of the timekeeper events having a particular frequency based on the information stored in the register.

10. The system of claim 1 wherein the specified one of the events from the timekeeper is operable to automatically trigger an enable request to the module in the low-power sleep mode, and wherein, in response to the enable request, the module processes the event and then returns to the low-power sleep mode.

2. A method for a battery management and protection system, the method comprising:

generating a plurality of events by a timekeeper, wherein each event has a frequency different from a frequency of the other events and is generated from a divided clock signal; and

passing the events from the timekeeper over a dedicated routing network directly to a module, wherein the module is programmed to respond to events having a particular frequency,

wherein, in response to a particular one of the events from the timekeeper generated while the system in is a low-power sleep mode and during which the module operates in a sleepwalking mode, the module is awakened from sleep independently of a central processing unit, obtains a signal indicative of an operational characteristic of a battery and determines whether the characteristic is within a predetermined range, and

wherein the module subsequently returns to sleep.

6. The method of claim 2 wherein, in response to receiving the event from the timekeeper, the module measures at least one of voltage or temperature of the battery and compares the measured voltage or temperature to a specified level.

7. The method of claim 2 wherein, in response to receiving the event from the timekeeper, the module measures current for the battery and determines whether the measured current is within a specified range.

8. The method of claim 2 wherein, in response to receiving the event from the timekeeper, the module samples voltages for the battery and compares the sampled voltages to a specified level.

11. The method of claim 2 wherein the module selects a particular one of the events having a predetermined frequency based on information stored in a dedicated input/output register storing information auto-loaded to the register during system start-up.

12. The method of claim 2 wherein the particular one of the events from the timekeeper automatically triggers an enable request to the module in the low-power sleep mode, and wherein, in response to the enable request, the module processes the event and then returns to the low-power sleep mode.