Dynamic voltage and frequency scaling circuits with two supply voltages

This paper presents circuits that enable dynamic voltage and frequency scaling (DVFS) for fine-grained chip multi-processors to reduce both dynamic and leakage power dissipation. Each processor can run on either a high voltage or low voltage power supply, or disconnect from both. Switching between power supplies is performed dynamically, where scaling decisions are based on each processor´s workload, allowing for reduced power consumption without a significant impact on performance. Tradeoffs in performance versus circuit area and supply noise are examined. The DVFS circuits are designed in a wrapper around each individual processor, resulting in a 12% area overhead. DVFS operation utilizing supply voltages of 1.3 V and 0.8 V on a nine-processor JPEG application reduces average energy consumption by 48% while reducing performance by only 8%.