Which is the best dual-port SRAM in 45-nm process technology? — 8T, 10T single end, and 10T differential —

This paper compares readout powers and operating frequencies among dual-port SRAMs: an 8T SRAM, 10T single-end SRAM, and 10T differential SRAM. The conventional 8T SRAM has the least transistor count, and is the most area efficient. However, the readout power becomes large and the cycle time increases due to peripheral circuits. The 10T single-end SRAM is our proposed SRAM, in which a dedicated inverter and transmission gate are appended as a single-end read port. The readout power of the 10T single-end SRAM is reduced by 75% and the operating frequency is increased by 95%, over the 8T SRAM. On the other hand the 10T differential SRAM can operate fastest, because its small differential voltage of 50 mV achieves the high-speed operation. In terms of the power efficiency, however, the sense amplifier and precharge circuits lead to the power overhead. As a result, the 10T single-end SRAM always consumes lowest readout power compared to the 8T and the 10T differential SRAM.