Regulator-gating
Selçuk Köse · 2014
Design-for-power has become one of the primary objectives with the continuous demand to improve the battery life of mobile devices or minimize the cooling costs of servers. To save power and mitigate thermal emergencies, circuits typically enter reduced power states when the workload is light. Voltage regulators, however, operate indifferently under varying workload conditions due to the lack of different operating modes. When a voltage regulator is optimized for a particular load current, significant power is dissipated during voltage conversion while delivering a different load current. Adaptive activity management of on-chip voltage regulators based upon the workload information is exploited in this paper to force each on-chip regulator to operate in its most power-efficient load current. In the proposed regulator-gating (ReGa) technique, regulators are adaptively turned on (off) when the current demand is high (low) to improve the voltage conversion efficiency. With the proposed ReGa technique, the overall voltage conversion efficiency from the battery or off-chip power supply to the output of on-chip voltage regulators is improved ~3x.