The Impact of Process Scaling on Scratchpad Memory Energy Savings

Scratchpad memories have been shown to reduce power consumption, but the different characteristics of nanometer scale processes, such as increased leakage power, motivate an examination of how the benefits of these memories change with process scaling. Process and application characteristics affect the amount of energy saved by a scratchpad memory. Increases in leakage as a percentage of total power particularly impact applications that rarely access memory. This study examines how the benefits of scratchpad memories have changed in newer processes, based on the measured performance of the WIMS (Wireless Integrated MicroSystems) microcontroller implemented in 180- and 65-nm processes and upon simulations of this microcontroller implemented in a 32-nm process. The results demonstrate that scratchpad memories will continue to improve the power dissipation of many applications, given the leakage anticipated in the foreseeable future.