there is an internal voltage generating circuit for providing a stable internal voltage by supplying the internal voltage before a time point when it is used . the internal voltage generating circuit includes a charge pump unit for generating an internal voltage lower than an external voltage in response to pumping control signals and a supply driving control signal ; a pumping control signal generating unit for outputting the pumping control signals to the charge pump unit based on a driving signal ; and a supply driving control unit for receiving the driving signal to generate the supply driving control signal to the charge pump unit .