Method of selective power cycling of components in a memory device independently by turning off power to a memory array or memory controller

• US 8,612,791 B2
• Filed: 06/14/2013
• Issued: 12/17/2013
• Est. Priority Date: 09/16/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Wakrat, Nir Jacob, Fai, Anthony, Byom, Matthew
• Primary Examiner(s): Lee, Thomas
• Assistant Examiner(s): JOHNSON, TERRELL S
• Application Number:
  US13/918,240
• Publication Number:
  US 20130283081A1
• Time in Patent Office: 186 Days
• Field of Search: 713/300, 713/324
• US Class Current: 713/324
• CPC Class Codes: G06F 1/3225 of memory devices
• CPC Class Codes: G06F 1/3275 Power saving in memory, e.g. RAM, cache
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

In a non-volatile memory system, physically separate power rails are provided from a host system to a NVM device for independently power cycling a controller and memory array in the NVM device. The controller of the NVM device can send a power cycle request signal to the host system over a host channel, or updates a status register in the NVM device. The host system receives and decodes the power cycle request signal, or reads the status register, and performs the power cycle request, which can include power cycling the controller or the memory array in the NVM device, or both. The power cycle request can be based on a power state of the non-volatile memory system, which can be managed by the controller or the host system, or both.

Claims

1. A method comprising:

reading, by a host, a status register in a controller of a non-volatile memory device to determine whether a power cycle request has been made by the non-volatile memory device;

decoding, by the host, contents of the status register; and

power cycling, by the host, at least one of the controller or a memory array of the non-volatile memory device based on the status register contents, wherein the power cycling includes turning off the power to a first power rail coupled to the controller.

2. The method of claim 1, wherein power cycling further includes turning off the power or reducing the power to a second power rail coupled to the memory array.

3. The method of claim 1, wherein the non-volatile memory device comprises a managed NAND device.

4. The method of claim 1, wherein the power cycle request is based on a power state.

5. The method of claim 1, wherein the power cycle request includes the controller updating the contents of the status register.

6. A non-volatile memory system, comprising:

a host system;

a non-volatile memory device coupled to the host system;

a memory array included in the non-volatile memory device and coupled to a power source in the host system by a first power rail; and

a controller within the non-volatile memory device and coupled to the power source by a second power rail;

wherein the controller is configured to update contents of a status register in the controller, and the host system is configured to read the status register and perform a power cycle on the first power rail or the second power rail based on the contents of the status register, wherein performing the power cycling includes removing the power from the first power rail.

7. The system of claim 6, wherein the non-volatile memory device is a managed NAND device.

8. The system of claim 6, wherein the power cycle is based on a power state of the non-volatile memory system.

9. The system of claim 6, wherein the non-volatile memory device includes a number of memory arrays, at least two of which can be power cycled through the first power rail.

10. The system of claim 6, wherein performing the power cycling includes removing the power from the second power rail.

11. The system of claim 6, wherein performing the power cycling includes reducing the power to the second power rail.