Low power electronic system architecture using non-volatile magnetic memory

• US 8,719,610 B2
• Filed: 09/23/2008
• Issued: 05/06/2014
• Est. Priority Date: 09/23/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Nowak, Matthew Michael, Chua-Eoan, Lew, Kang, Seung H
• Primary Examiner(s): MISIURA, BRIAN THOMAS
• Application Number:
  US12/235,933
• Publication Number:
  US 20100077244A1
• Time in Patent Office: 2,051 Days
• Field of Search: 713/2, 713/300, 713/320, 713/324
• US Class Current: 713/324
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3275 Power saving in memory, e.g. RAM, cache
• CPC Class Codes: G11C 11/16 using elements in which the storage effect is based on magnetic spin effect
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A computing system includes at least one functional unit and a magnetic random access memory (MRAM) block coupled to the at least one functional unit. The MRAM block is configured to store a functional state of the at least one functional unit during a power down state of the at least one functional unit.

Claims

1. A computing system comprising:

an internal section;

an external section coupled to the internal section;

at least one functional unit within the internal section;

a magnetoresistive random access memory (MRAM) block within the internal section and embedded in a substrate of the at least one functional unit, the MRAM block configured to store a functional state of the at least one functional unit during a standby state of the internal section; and

a volatile memory within the external section.

2. The computing system of claim 1 further comprising:

a random access memory (RAM) block coupled to the at least one functional unit and the MRAM block, wherein the RAM block is configured to store a portion of the functional state of the at least one functional unit during a power on state of the at least on functional unit, and wherein the MRAM block is further configured to store the portion during the power down state.

3. The computing system of claim 2 further comprising:

a data mover block configured to transfer the portion of the functional state located in the RAM into the MRAM block during the power down state.

4. The computer system of claim 1 wherein the MRAM block is a spin torque transfer (STT) MRAM block.

5. The computing system of claim 1 wherein the functional state comprises a plurality of data representing the functional state of the at least one functional unit.

6. The computing system of claim 1 wherein the MRAM block comprises an STT MRAM chip and the at least one functional unit comprises at least one functional unit chip.

7. A method comprising:

receiving a standby signal within a computing system including an internal section, and an external section coupled to the internal section, the standby signal requesting the internal section, including one or more functional units, to enter a standby state during operation of the external section;

responsive to receiving the standby signal, storing a first portion of a current operational state from the one or more functional units in a magnetic random access memory (MRAM) embedded in a substrate of the one or more functional units, and storing, in the MRAM, a second portion of the current operational state from the internal section; and

removing power from the internal section including the one or more functional units after the current operational state is stored.

8. The method of claim 7 further comprising:

receiving a wake-up signal requesting the one or more functional units in the standby mode to enter an operating mode;

responsive to receiving the wake-up signal, restoring the power to the one or more functional units in the standby mode; and

reinstating the current operational state to the one or more functional units.

9. The method of claim 7 wherein the storing comprises:

scanning the one or more functional units for data defining the first portion of the current operational state;

transmitting the data defining the first portion of the current operational state from the one or more functional units to the MRAM; and

transferring additional data defining the second portion of the current operational state from a random access memory (RAM) coupled to the one or more functional units to the MRAM.

10. The method of claim 9 further comprising:

receiving a wake-up signal requesting the one or more functional units in the standby mode to enter an operating mode;

in response to the wake-up signal, restoring the power to the one or more functional units in the standby mode;

loading the data defining the first portion of the current operational state from the MRAM into another portion of the one or more functional units; and

reinstating the additional data defining the second portion of the current operational state from the MRAM into the RAM.

11. The method of claim 7 wherein the storing comprises:

storing data defining the first portion of the current operational state of the one or more functional units in one or more magnetic memories associated with one or more latches in a processing path of the one or more functional units; and

transferring additional data defining the second portion of the current operational state from a random access memory (RAM) coupled to the one or more functional units to the MRAM.

12. The method of claim 11 further comprising:

receiving a wake-up signal requesting the one or more functional units in the standby mode to enter an operating mode;

in response to the wake-up signal, restoring the power from the power supply to the one or more functional units in the standby mode;

loading the data defining the first portion of the current operational state from the one or more magnetic memories into the one or more functional units; and

reinstating the additional data defining the second portion of the current operational state from the MRAM into the RAM.

13. The method of claim 7 wherein the removing the power comprises one or both of:

switching off a power supply coupled to the one or more functional units; and

creating an open circuit between the power supply and the one or more functional units.

14. A system comprising:

means for receiving a standby signal within a computing system including an internal section and an external section coupled to the internal section, the standby signal requesting the internal section, including one or more functional units, to enter a standby state during operation of the external section;

responsive to the standby signal, means for storing a first portion of a current operational state of the one or more functional units in a magnetic random access memory (MRAM) embedded in a substrate of the one or more functional units, and means for storing, in the MRAM, a second portion of the current operational state from the internal section;

means for removing power from the internal section, including the one or more functional units after the current operational state is stored;

means for receiving a wake-up signal requesting the one or more functional units in the standby mode to enter an operating mode;

responsive to the wake-up signal, means for restoring the power to the one or more functional units in the standby mode; and

means for reinstating the current operational state to the one or more functional units.

15. The system of claim 14 wherein the means for storing comprises:

means for scanning the one or more functional units for data defining the first portion of the current operational state;

means for transmitting the data defining the first portion of the current operational state from at least one section of the one or more functional units to the MRAM; and

means for transferring additional data defining the second portion of the current operational state from a random access memory (RAM) coupled to the one or more functional units to the MRAM.

16. The system of claim 15 further comprising:

means for loading the data defining the first portion of the current operational state from the MRAM into the one or more functional units; and

means for reinstating the additional data defining the second portion of the current operational state from the MRAM into the RAM.

17. The system of claim 14 wherein the means for storing comprises:

means for storing data defining the first portion of the current operational state located in the one or more functional units in one or more magnetic memories associated with one or more latches; and

means for transferring additional data defining the second portion of the current operational state from a random access memory (RAM) coupled to the one or more functional units to the MRAM.

18. The system of claim 17 further comprising:

means for loading the data defining the first portion of the current operational state from the one or more magnetic memories into the one or more functional units; and

means for reinstating the additional data defining the second portion of the current operational state from the MRAM into the RAM.

19. The system of claim 14 wherein the means for removing the power comprises one or both of:

means for switching off a power supply coupled to the one or more functional units; and

means for creating an open circuit between the power supply and the one or more functional units.

20. A computing system comprising:

an internal section;

an external section coupled to the internal section;

at least one functional unit within the internal section;

means for placing the internal section into a standby state during operation of the external section; and

means for storing a functional state of the at least one functional unit, prior to placing the internal section into the standby state, during operation of the external section, the storing means within the internal section and embedded in a substrate of the at least one functional unit.