Patent attributes
An A/D (analog-to-digital) conversion circuit includes an input signal selecting circuit configured to output voltage signals of different signal levels in response to control signals in an adjustment mode before A/D conversion of an analog signal in a practical mode; an A/D converter configured to perform A/D conversion on the voltage signals in response to an adjustment sampling clock signal in the adjustment mode to output adjustment conversion values; and a sampling timing adjusting circuit configured to delay a reference sampling clock signal based on a delay value selected in response to a selection signal in the adjustment mode to output the adjustment sampling clock signal to the A/D converter. An operation circuit is configured to set the adjustment mode, output the control signals to the input signal selecting circuit, and the selection signal to the sampling timing adjusting circuit, such that the adjustment conversion values are obtained at each of different delay values, determine an optimal parameter from parameters corresponding to the obtained adjustment conversion values, and set the practical mode to output the selection signal corresponding to the optimal parameter to the sampling timing adjusting circuit.
