The SST37VF512/010/020/040 devices are 64K x8 / 128K x8 / 256K x8 / 512K x8 CMOS, Many-Time Programmable (MTP), low cost flash, manufactured with SST's proprietary, high performance CMOS SuperFlash technology. The split-gate cell design and thick-oxide tunneling injector attain better reliability and manufacturability compared with alternate approaches. The SST37VF512/010/020/040 can be electrically erased and programmed at least 1000 times using an external programmer, e.g., to change the contents of devices in inventory. The SST37VF512/010/020/040 have to be erased prior to programming. These devices conform to JEDEC standard pinouts for byte-wide flash memories.