Patent attributes
In view of controlling overshoot when the power supply is inputted without increase in the area occupied with a chip in a voltage generating circuit mounted over a semiconductor integrated circuit, an internal voltage generating circuit comprises a voltage generating circuit for generating a second voltage from a first voltage supplied from outside, and an output buffer for generating a third voltage corresponding to the second voltage. The third voltage is used as the operation power supply of the internal circuit. Moreover, a first switch for enabling an output node of the second voltage to become conductive to the predetermined potential and a control circuit for turning ON the first switch for the predetermined period in response to input of the first voltage are also provided. An output terminal of the output buffer is not clamped but an output of the voltage generating circuit in the preceding stage is clamped to the predetermined voltage. The transistor of the first switch for clamping the voltage may be remarkably reduced in size in comparison with an output transistor of the output buffer. Accordingly, the area occupied by the chip is not enlarged.