Apparatus, system and method for control of speed of operation and power consumption of a memory

摘要

This invention concerns power consumption control of memory having a fully powered state and at least one lower power state. The invention changes the memory to the fully powered state upon receipt of a memory access request. This memory access request is serviced in the fully powered state. The memory is returned to a lower power state after expiration of a grace period following a last memory access request. This grace period can be measured by a predetermined time or a predetermined number of memory access requests or a combination of these factors. The predetermined time may be fixed in manufacture or programmable in operation via a control register or data stored in a predetermined set of address locations within the address space of the memory. This invention is useful in portable electronic devices such as wireless telephones.