| 摘要 |
<p>PROBLEM TO BE SOLVED: To attain a satisfactory rewrite operation, regardless of the variance of power voltage in a rewrite mode by generating the voltage via a voltage generating circuit based on the power voltage. SOLUTION: When 1st and 2nd pulse signals of a boosting pulse signal CLK that is generated by a boosting pulse generator 3 are set at 'H' and 'L' respectively, the potential of a power line VPI rises. When the 1st and 2nd pulse signals are set at 'L' and 'H' respectively, the charge value is accumulated and transmitted to the line VPI from a power voltage Vcc. Then a high voltage is supplied to the outside of a positive voltage generation part 4 through the line VPI. Thus, the high voltage set based on the voltage Vcc is outputted to the line VPI from the part 4, and the line VPI is controlled at a fixed voltage level by a 1st voltage control circuit 1. The voltage state applied to a memory cell in a rewrite mode is varied according to the power voltage, and the difference of applied voltage is kept constant.</p> |
