ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY

An Electrically Erasable Programmable Read-Only Memory (EEPROM) requires only a single voltage applied to a single control gate for both erasing and writing operations. Writing is accomplished by hot channel electron injection to charge the floating gate of a selected device with electrons. Nonselected devices are kept from charging by either floating their sources or grounding their gates. Devices are erased by grounding the source and drain regions and causing the electrons stored in the floating gates to tunnel to the control gate. Preferred ratioing of the intra-device capacitances prevents erasure of nonselected devices during writing.