| 摘要 |
PROBLEM TO BE SOLVED: To provide the signal input circuit, from which a correct digital output is obtained from an input signal on which a noise signal is superimposed. SOLUTION: The circuit is made up of integration circuits 1, 2, a differential amplifier 3 and a latch circuit 4. An input signal and a reference signal are respectively inputted to the integration circuits 1, 2. The respective signals integrated for each predetermined integration time by the integration circuits 1, 2 are inputted to the differential amplifier 3, in which their difference is obtained. The output of the differential amplifier 3 is inputted to the latch circuit 4, from which a digital signal is outputted for each prescribed timing. The integration circuits 1, 2 integrate the input signal and the reference signal analogically for a period, prior to the input signal voltage being compared with the reference voltage. In the case that the input signal and the reference voltage are integrated analogically, the noise signal superimposed at random is averaged and cancelled to eliminate the effect of the noise. |
