Calibration circuit and calibration apparatus including the same

A calibration apparatus comprising:

• a first calibration circuit configured to perform an impedance matching operation according to a resistor for impedance matching in response to a first calibration enable signal generated by decoding a command signal, and generate a completion signal when performance is completed;
• and
• a second calibration circuit configured to share the resistor for the impedance matching with the first calibration circuit, and perform an impedance matching operation according to the completion signal.

A calibration circuit, comprising:

• a selector configured to select a calibration enable signal or a start signal in response to a select signal to provide a driving signal;
• a calibration driver configured to perform an impedance matching operation according to the driving signal and generate a completion signal,
• wherein the calibration driver performs the impedance matching operation by comparing a value received from a resistor for impedance matching to a reference value for generating a matching code.