Cache controller design on ultra low leakage embedded processors

A leakage-efficient cache controller design targeted on ultra low power embedded processors is proposed. The key insight is that a large circuits subset is accessed only when cache misses happen. By utilizing the fine-grained run-time power gating technique, such a subset can be dynamically powered-off as a power gated domain. Two simple but effective sleeping control policies are proposed to assure the leakage reduction effect; and to eliminate the impact of wake-up process, a latency cancellation mechanism is also proposed. Evaluation results show, in 90nm CMOS technology, 69% and 64% of leakage power can be reduced for instruction cache controller and data cache controller without performance degradation.