The ON Semiconductor serial SRAM family includes severalintegrated memory devices including this 1Mb serially accessed StaticRandom Access Memory, internally organized as 128 K words by8 bi t s . The devices are designed and fabricated usingON Semiconductor’s advanced CMOS technology to provide bothhigh-speed performance and low power. The devices operate with asingle chip select (CS) input and use a simple Serial PeripheralInterface (SPI) protocol. In SPI mode, a single data-in (SI) anddata-out (SO) line is used along with the clock (SCK) to access datawithin the device. In DUAL mode, two multiplexed data-in/data-out(SIO0-SIO1) lines are used and in QUAD mode, four multiplexeddata-in/data-out (SIO0-SIO3) lines are used with the clock to accessthe memory.The devices can operate over a wide temperature range of −40°C to+85°C and are available in a 8-lead TSSOP package.