PROGRAMMABLE NON-VOLATILE SEMICONDUCTOR MEMORY

• Main Author: OKUBO HIDE
• Format: Patent
• Language: English
• Published: 25.02.1992
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INFORMATION STORAGE; PHYSICS; SEMICONDUCTOR DEVICES; STATIC STORES

PURPOSE:To realize a multilevel memory by reading a memory cell when the memory cell is programmed, comparing the data with an input data and continu ing a programming operation until the write state of the memory cell is matched with the input data. CONSTITUTION:When a program control signal is made L, a program pulse PHIpgm is outputted from a pulse generating circuit 38. With this program pulse PHIpgm, a program pulse PHIp is outputted from an AND circuit 40. According to the level of the pulse PHIp, a power supply voltage Vpp and a power supply voltage Vcc are alternately outputted from a switching circuit 20. The Vpp is impressed to a Y gate 24 of a word line 160 to be designated by an address to be impressed from the outside. According to the input data impressed from the outside, an inverter 30 supplies a high voltage approximate to the Vpp or a GND potential through a NOR circuit 37 and a NAND circuit 36 to a bit line 22. Then, the input data is written.