Patent ID: 6373326
Filing Date: 2002-04-16
Classification: G11C

Abstract:
A writing circuit comprising:a writing control circuit for outputting an oscillation instruction signal for instructing a start of oscillation in response to an external signal, and a period setting signal for setting a time after the start of oscillation at which a first boosted voltage is compared to a second boosted voltage; an oscillation circuit for effecting an oscillating operation in response to the oscillation instruction signal so as to output clock signals; a first charge pump circuit for boosting a power supply voltage in response to the clock signals so as to generate the first boosted voltage; a second charge pump circuit for boosting the power supply voltage in response to the clock signals to generate the second boosted voltage; a voltage detecting circuit for comparing the first boosted voltage with the second boosted voltage so as to determine if the first boosted voltage reaches a desired voltage value and for outputting discrimination signals for instructing the oscillation circuit to stop the oscillating operation if the desired voltage value is not reached.