Memory circuit system and method

• US 8,209,479 B2
• Filed: 10/30/2007
• Issued: 06/26/2012
• Est. Priority Date: 07/18/2007
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Rajan, Suresh Natarajan, Schakel, Keith R., Smith, Michael John Sebastian, Wang, David T., Weber, Frederick Daniel
• Primary Examiner(s): Campos, Yaima
• Application Number:
  US11/929,571
• Publication Number:
  US 20090024789A1
• Time in Patent Office: 1,701 Days
• Field of Search: 711/105, 711/167, 711170-173, 703/21, 703/28, 365/189.2, 365/194, 365/209
• US Class Current: 711/105
• 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: G06F 12/0215 with look ahead addressing means
• CPC Class Codes: G06F 2212/1028 Power efficiency
• 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 memory circuit system and method are provided in the context of various embodiments. In one embodiment, an interface circuit remains in communication with a plurality of memory circuits and a system. The interface circuit is operable to interface the memory circuits and the system for performing various functionality (e.g. power management, simulation/emulation, etc.).

Claims

1. A memory apparatus for use with a host system, the memory apparatus comprising:

a first plurality of memory circuits; and

an interface circuit operable to interface the first plurality of memory circuits and the host system, and to present to the host system one or more emulated memory circuits, the interface circuit including;

a first component of a first type; and

a second component of a second type, the first and the second components being operable to present, in combination, a host-system interface to the host system and to present, in combination, a memory-circuit interface to the first plurality of memory circuits, where at least one aspect of the host-system interface is different from a respective corresponding aspect of the memory-circuit interface, where the at least one aspect of the host-system interface and the respective corresponding aspect of the memory-circuit interface each include at least one of a signal, a memory capacity, or a timing,

where each memory circuit of the first plurality of memory circuits is electrically coupled to the second component,

where the first component is operable to receive (1) address signals and (2) control signals other than address signals from the host system and send at least one of the control signals received from the host system to the second component, and where the second component is operable to receive a first set of data signals from the host system and send the first set of data signals received from the host system to at least one memory circuit of the first plurality of memory circuits.

2. The memory apparatus of claim 1, where the at least one of the control signals includes a power management signal.

3. The memory apparatus of claim 2, where the power management signal is associated with a power saving operation.

4. The memory apparatus of claim 3, where the power saving operation includes a power off operation, an operation to reduce current, or an operation to reduce voltage.

5. The memory apparatus of claim 2, where the power management signal is an encoded signal.

6. The memory apparatus of claim 1, where the second component is operable to send the first set of data signals to the at least one memory circuit of the first plurality of memory circuits after a delay.

7. The memory apparatus of claim 6, where the delay is a fraction of a clock cycle.

8. The memory apparatus of claim 7, where the delay is one half clock cycle delay.

9. The memory apparatus of claim 1, further comprising:

a second plurality of memory circuits different from the first plurality of memory circuits; and

a third component of the second type, where the first component is operable to send a second set of the address and control signals received from the host system to the third component, and where the third component is operable to receive a second set of data signals from the host system and send the second set of data signals received from the host system to at least one memory circuit of the second plurality of memory circuits.

10. The memory apparatus of claim 9, further comprising:

a first buffered stack that includes the first plurality of memory circuits, where the first plurality of memory circuits is coupled to the second component; and

a second buffered stack that includes the second plurality of memory circuits, where the second plurality of memory circuits is coupled to the third component.

11. The memory apparatus of claim 10, further comprising a dual-inline memory module (DIMM), where the DIMM includes the first component, the first buffered stack and the second buffered stack.

12. The memory apparatus of claim 10, where the first component is electrically coupled to the first buffered stack and to the second buffered stack.

13. The memory apparatus of claim 1, where the first type of component is a register and the second type of component is a buffer.

14. The memory apparatus of claim 1, further comprising a dual-inline memory module (DIMM), where the DIMM includes the first plurality of memory circuits, the first plurality of memory circuits being coupled to the DIMM.

15. The memory apparatus of claim 14, where the DIMM includes the second component.

16. The memory apparatus of claim 15, where DIMM includes the first component.

17. The memory apparatus of claim 14, where the first plurality of memory circuits comprises a stack of dynamic random access memory (DRAM) circuits.

18. The memory apparatus of claim 17, where the DIMM comprises a plurality of address, control and clock buses.

19. The memory apparatus of claim 17, where the DIMM comprises a single shared address, control and clock bus coupled to each memory circuit of the first plurality of memory circuits in the stack.

20. The memory apparatus of claim 17, where the DIMM comprises a shared data bus coupled to two or more memory circuits of the first plurality of memory circuits.

21. The memory apparatus of claim 17, where the DIMM comprises a plurality of data buses, each data bus of the plurality of data buses being coupled to two or more memory circuits of the first plurality of memory circuits.

22. The memory apparatus of claim 17, where the DIMM comprises a plurality of data buses, each data bus of the plurality of data buses being respectively coupled to a different memory circuit of the first plurality of memory circuits.

23. The memory apparatus of claim 1, where the at least one aspect of the host-system interface is associated with a first signal relating to a mode register operation and the respective corresponding aspect of the memory-circuit interface is associated with a second different signal relating to the mode register operation.

24. The memory apparatus of claim 1, where the at least one aspect of the host-system interface is associated with a first memory capacity and the respective corresponding aspect of the memory-circuit interface is associated with a second different memory capacity.

25. The memory apparatus of claim 1, where the at least one aspect of the host-system interface is associated with a first number of memory circuits and the respective corresponding aspect of the memory-circuit interface is associated with a second different number of memory circuits.

26. The memory apparatus of claim 1, where the at least one aspect of the host-system interface is associated with a first operation latency and the respective corresponding aspect of the memory-circuit interface is associated with a second different operation latency.

27. The memory apparatus of claim 1, where the at least one aspect of the host-system interface is associated with a first number of banks and the respective corresponding aspect of the memory-circuit interface is associated with a second different number of banks.

28. The memory apparatus of claim 1, where at least one of the first or second components is operable to:

select one or more memory circuits of the first plurality of memory circuits by generating one or more chip select signals; and

perform an operation on the one or more selected memory circuits.

29. The memory apparatus of claim 1, where at least one of the first or second components is further operable to:

identify one or more memory circuits of the first plurality of memory circuits that is not being accessed; and

perform a power-saving operation on the one or more memory circuits identified as not being accessed.

30. The memory apparatus of claim 29, where the at least one of the first or second components is operable to perform the power-saving operation by placing at least one memory circuit of the one or more memory circuits identified as not being accessed in a precharge power down mode.

31. The memory apparatus of claim 30, where the at least one of the first or second components is operable to place the at least one memory circuit of the one or more memory circuits identified as not being accessed in a precharge power down mode by controlling a clock enable input of the at least one memory circuit.

32. The memory apparatus of claim 29, where the at least one of the first or second components is operable to identify the one or more memory circuits as not being accessed based on how many pages are open in at least one memory circuit of the first plurality of memory circuits.