The SST27SF256/512/010/020 are a 32K x8 / 64K x8 / 128K x8 / 256K x8 CMOS, Many-Time Programmable (MTP) low cost flash, manufactured with SST's proprietary, high performance SuperFlash technology. The split-gate cell design and thick oxide tunneling injector attain better reliability and manufacturability compared with alternate approaches. These MTP devices can be electrically erased and programmed at least 1000 times using an external programmer with a 12 volt power supply. They have to be erased prior to programming. These devices conform to JEDEC standard pinouts for byte-wide memories. Featuring high performance Byte-Program, the SST27SF256/512/010/020 provide a Byte-Program time of 20 s. Designed, manufactured, and tested for a wide spectrum of applications, these devices are offered with an endurance of at least 1000 cycles. Data retention is rated at greater than 100 years.