Clock gating coupled memory retention circuit

Abstract

A hierarchy of interconnected memory retention (MR) circuits detect a clock gating mode being entered at any level of an integrated circuit. In response, the hierarchy automatically transitions memory at the clock gated level and all levels below the clock-gated level from a normal operating state to a memory retention state. When a memory transitions from a normal operating state to a memory retention state, the memory transitions from a higher power state (corresponding to the normal operating state) to a lower power state (corresponding to the memory retention state). Thus, in addition to the dynamic power savings caused by the clock gating mode, the hierarchy of MR circuits automatically transitions the memory modules at the clock gated level and all levels below the clock gated level to a lower power state. As a result, the leakage power consumption of the corresponding memory modules is reduced relative to prior approaches.