| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a semiconductor device with a built-in boosting circuit, capable of making full use of voltage boosting capability required in a wide range of power supply voltage and suppressing generation of overshoot and ripple. SOLUTION: The boosting circuit 11 is constituted of a plurality of stages of boosting units and is divided into an area A on a power supply load side and regions B, C on a boosting output terminal side. A boosting pulse FAIa, outputted from an oscillator 13, is given to the boosting circuit 11 as boosting pulses FAIb, FAIc, and FAId, whose amplitudes are limited in the optimum clamp levels for the respective regions A, B, and C by a clamp circuit 14 to which two clamp reference voltages CLref1, CLref2 are inputted. The amplitude limit of the FAIb supplied to the region A is small, while the amplitude limit of the FAIc or FAId supplied to the region B or C is large. A limiter circuit 12 switches the clamp level of the boosting pulse FAIc or FAId given to the region B or C, based on a flag signal ENB2 generated in the course of the boosting operation.</p> |
