Threshold value setting circuit for a video signal interface and to recording apparatus provided therewith.

摘要

A threshold value setting circuit of a video signal interface comprises a voltage comparator (2,64) which receives a luminance signal (1,66) and converts the luminance signal into a logic signal (68). A discrimination circuit (4) discriminates the output of the voltage comparator (2,64). A digital-analog conversion circuit (3) sets the threshold value of the voltage comparator (2,64) to an arbitrary value. In operation the output of the voltage comparator (2,64) for the set threshold value is discriminated, the setting of the reference voltage is sequentially changed in accordance with the result of discrimination, and a threshold value which is in agreement with a peak voltage of the luminance signal (66) is determined in order to measure the signal voltage of the luminance signal.