A 1.85fW/bit ultra low leakage 10T SRAM with speed compensation scheme

A low leakage memory is an indispensable part of any sensor application that spends significant time in standby (sleep) mode. Although using high Vth (HVT) devices is the most straightforward way to reduce leakage, it also limits operation speed during active mode. In this paper, a low leakage 10T SRAM cell, which compensates for operation speed using a readily available secondary supply, is proposed in a 0.18µm CMOS process. It achieves the lowest-to-date leakage power consumption and achieves robust operation at low voltage without sacrificing operation speed. The 10T SRAM has a bitcell area of 17.48µm2 and is measured to consume 1.85fW per bit at 0.35V.

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