| 摘要 |
A voltage supply circuit in which parasitic oscillation of a charge pump driver circuit can be restrained, charge pump driving currents can be generated at a stable oscillation frequency, and a desired boosting voltage can be supplied to a load circuit. Because oscillation voltage VOSC having an oscillation frequency unique to a crystal oscillator is generated by oscillator circuit 10, charge pump driver circuit 20a is provided with comparator CMP2 having a hysteresis characteristic, comparator CMP2 does not operate when output differential voltage DeltaVi of comparator CMP1 is lower than prescribed threshold DeltaVth, and comparator CMP2 begins to operate when DeltaVi has exceeded threshold DeltaVth in order to generate driving currents IS1 and IS2 having the same frequency as that of the oscillation signal output by oscillator circuit 10 and supplies them to charge pump circuit 30, parasitic oscillation can be restrained, and driving currents having a desired frequency can be supplied to the charge pump circuit using a simple circuit configuration.
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