Circuit for programming a flash EEPROM and method of programming a flash EEPROM using the same

摘要

PURPOSE: A program circuit of a flash EEPROM and a programming method utilizing the same are provided to confirm the minimum and maximum values of a threshold voltage of a flash memory cell by comparing a plurality of reference voltages with the threshold voltage upon implementing a program. CONSTITUTION: The program circuit of a flash EEPROM comprises a program time determining circuit(12), a register(13), a program section(14), a reference voltage generating section(15) and a comparing section(16). The program time determining circuit(12) determines the time required to program a memory cell(11) according to a target threshold voltage. The register(13) stores data concerning the program time determined by the program time determining circuit(12). The program section(14) programs the memory cell(11) for a predetermined period of time according to the data stored in the register(13) and increases a threshold voltage of the memory cell(11) up to the target threshold voltage. The comparing section(16) determines the level of the threshold voltage of the memory cell(11).