Abstract: A flash memory EEPROM device with a programming current limiting ability operates with six terminals and includes a source-side injection cell and a current limiter in series with the cell at a source region of the cell. During programming, an upper current limit is established for the overall channel current through the cell by controlling the voltage on a serial-gate of the current limiter. A second embodiment of a flash memory EEPROM device is structured with only four operating terminals, and includes a current limiting transistor integrally merged with a source-side injection cell. Merger is accomplished by eliminating the source junction of the injection cell and by combining the select-gate of the injection cell with the serial-gate of the current limiting transistor to create a conjoint select-gate. The unified channel under the conjoint select-gate consists of two channel sub-sections with different threshold adjustment implants and thus different threshold voltages.

Abstract: For negative gate erase and programming of non-volatile floating gate EEPROM devices, large positive or negative voltages from one single negative charge pump and from one single positive charge pump are selectively switched onto a one or more memory sectors of twin-well CMOS negative-gate-erase memory cells. The control gate is negative during erasing and positive during programming. In order for FLASH memories to have minimum layout area, small sectors or arrays of EEPROM cells can be erased all at once using a charge pump which includes two pump capacitors to provide negative voltages to the gate terminals of one or more series PMOS transistors.

Abstract: A flash EPROM memory array which operates at lower voltage power supply with no disturbance during operation. The memory circuit comprises a plurality of memory elements in a matrix fashion with each element including a semiconductor substrate, a drain region, a source region, a floating gate, a control gate, and a select gate. The low voltage power supply operation capability is achieved by a special arrangement on the said memory array such that the programming of the memory cell is achieved by high efficient hot electron injection which allows lower drain voltage during programming. No disturbance during program and erase occurs due to a control gate line running in parallel with the drain line. No disturbance access during read operation because of alternating drain and source lines such that the memory device can be read from the source side.