The PSoC devices utilizes a unique flash process called SONOS ( Silicon Oxide Nitrous Oxide Silicon Semiconductor). So, the flash erase in the PSoC device turns on all the memory transistors in an array or array portion (such as a row in Flash). Erased transistor = negative Vt = “on” = “0”. Programming the flash turns off only those memory transistors that must become “ones”. Programmed transistor = positive Vt = “off” = “1. ”Thus, after erasing, the flash content is changed to zero.
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