| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor which mounts a boosting circuit taking an optimum action, according to load capacity. SOLUTION: The time constant of the waveform at a rise in boosted potential VPP is monitored at real time by measuring a time when boosted potential VPP reaches a specified reference potential by means of a system clock CLKS. When the measured time is shorter than the time recorded in advance in a ROM66, a control unit 68 adjusts the driving force of a boosting circuit 50 by lessening the amplitude of a clockϕ. Hereby, even in case that the relative relation between driving force and load changes by power voltage, load capacity, and other factors, the driving force can be optimized. That is, even if information such a power voltage, the number of selected bit lines, etc. are not given from outside, the driving force is adjusted autonomously, and current consumption and improvement of ripple quantity are achieved. COPYRIGHT: (C)2005,JPO&NCIPI
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