Control circuit for eeprom

Abstract

Abstract PURPOSE:To simplify the titled circuit and to attain a low voltage action by operating a control circuit with a low frequency clock pulse and using a boosting circuit with many FET boosting stages and a high-voltage shaping switching circuit. CONSTITUTION:A low frequency clock pulse oscillating circuit 11 is operated with a low voltage and a low current, and oscillates the pulse of around 30kHz. A boosting circuit 12 consists of a boosting stage FET with >=19 stages, is driven by the circuit 11, and obtains a direct current voltage of about 20V to an output voltage. A high-voltage shaping switching circuit 13 has the rise characteristics of an exponential type, and forms the direct current voltage of about 20V obtained at the circuit 12 into a high-voltage pulse necessary for the writing and erasing of a memory cell 16. By such a constitution, the high voltage necessary for the writing of an EEP-ROM cell 14 can be obtained from the low voltage, and further, a waveform shaping circuit is made unnecessary, and the circuit can be simplified.

Inventors

• 👤 Koji Tanagawa

Bibliographic Details