Input buffer for generating output signal having DC voltage component to be controlled as a predetermined voltage and AC voltage component to be quickly responded to that of input signal

摘要

PURPOSE: An input buffer for controlling a DC voltage component of an output signal as a setup voltage and performing a rapidly respondent operation for an AC voltage component of an input signal are provided to minimize a variation of DC voltage level according to a variation of a process condition by reflecting rapidly a variation of AC component of a buffer input signal. CONSTITUTION: An AC voltage response circuit(100) is used for amplifying an AC voltage component of an input signal(VIN) and generating a buffer output signal(VOUT). A DC voltage reflection circuit(200) is used for providing a DC voltage reflection signal(DCF) having the same level as the buffer output signal(VOUT). A reference voltage generation portion(400) generates a reference voltage(DCR). A comparator(300) is used for comparing the DC voltage reflection signal(DCF) with the reference voltage(DCR) and generating a control signal(REFP).