Non-volatile multi-state memory device with memory cell capable of

Abstract

Inputted digital data are held in a data register and converted to multi-state analog amount by a resistance dividing circuit and a decoder. A comparator compares an analog amount read from a non-volatile memory cell with a converted analog amount; and in accordance with this comparison result, a writing voltage is supplied to a memory cell. A first bias generating circuit is provided for generating two different types of bias voltages as this writing voltage, MOS transistors are inserted as respective switches to the bias voltage supply lines and writing voltages are switched by selectively ON/OFF-controlling one of the MOS transistors in accordance with the upper bit of the inputted digital data. As a result, unnecessary writing time can be eliminated, time required for executing writing can be reduced and circuit configuration can be simplified.