OUTPUT PROCESSING SYSTEM OF POTENTIAL SENSOR

PURPOSE:To obtain a stable output reduced in fluctuation and to introduce the same into a microcomputer system by mounting a range change-over circuit automatically changing over an output signal level according to the levels of the input signals from the first and second electrodes. CONSTITUTION:An automatic range change-over circuit is added at the post- stage of a DC amplifier of a conventional example. This change-over circuit is equipped with four kinds of range circuits 51 - 54 of unit, double, quadruple and octuple, four comparators 61 - 64 dividing source voltage Vcc to set reference voltages and comparing said voltages with an input signal level, a decoder 71 decoding the outputs of the comparators 61 - 64 and a switch circuit 72 selecting either one of the signals of the circuits 51 - 54 based on a command from the decoder 71 and outputting the same. The input signal level is compared with respective reference voltages by the comparators 61 - 64 and judged. As a result, the decoder 71 controls the circuit 72 to select either one of the circuits 51 - 54 and to output a signal therefrom and also outputs range data showing which range is selected.