On-chip Adaptive Voltage Scaling Based on Flexible Critical Path Emulation Enabled by Buck Converter

Adaptive voltage scaling (AVS) is commonly used to reduce power consumption of digital load. Conventional on-chip AVS is realized by replica the critical path of a load, which has the longest delay time during one clock circle. However, relying on the longest critical path cannot get the maximum energy saving. This paper proposes a flexible critical path emulation (FCPE) technique to maximum energy saving of AVS. In order to compose the whole AVS circuit, a buck converter is used to regulate voltage, and a load which can perform three different operations is considered. Regulating range of voltage is set at 0.7V-1.8V in the proposed AVS converter. Simulation results and energy consumption curve of the AVS converter are both given out.