Semiconductor memory device having a sleep mode

摘要

The present invention provides a computer memory device having a sleep mode characterized by extremely low current consumption and relatively large turn on delay. The invention includes circuitry for disabling current sinking elements internal to said device in response to a sleep signal. In one embodiment, the invention includes circuitry for disconnecting the bit lines and memory cell loads of a nonvolatile static random access memory (nvSRAM) array from a source of power in response to a sleep signal. This embodiment is capable of first transferring the data stored in a volatile portion of the array to a nonvolatile portion of the array before entering sleep mode to prevent loss of the data.