A semiconductor memory apparatus includes: a skew monitoring unit configured to receive a reference voltage and monitor a voltage characteristic of a corresponding MOS transistor; a voltage sensing unit configured to provide a sensing voltage corresponding to the monitoring result of the voltage characteristic; a coding unit configured to multiplex an output signal of the voltage sensing unit and provide a skew control signal; and an internal voltage regulation unit configured to provide an internal voltage by regulating an internal bias voltage in response to the skew control signal.