A 512kb 8T SRAM Macro Operating Down to 0.57 V With an AC-Coupled Sense Amplifier and Embedded Data-Retention-Voltage Sensor in 45 nm SOI CMOS

摘要

An 8T SRAM fabricated in 45$,$ nm SOI CMOS exhibits voltage scalable operation from 1.2$,$V down to 0.57$,$V with access times from 400$,$ ps to 3.4$,$ ns. Timing variation and the challenge of low voltage operation are addressed with an AC-coupled sense amplifier. An area efficient data path is achieved with a regenerative global bitline scheme. Finally, a data retention voltage sensor has been developed to predict the mismatch-limited minimum standby voltage without corrupting the contents of the memory.