Impedance calibration circuit

Abstract

An impedance calibration circuit may include a first reference voltage generator configured to generate a first reference voltage in response to reference voltage calibration signals, a second reference voltage generator configured to provide a second reference voltage as a conversion voltage, an impedance calibration signal generator configured to compare the conversion voltage with the first reference voltage and generate impedance calibration signals when an enable signal is activated, and a register configured to store the impedance calibration signals finally calibrated and generate reference voltage calibration signals in response to the stored impedance calibration signals.

Dependencies are inferred from the claim text.