Multi-input comparator

PURPOSE: To improve relative precision by making a time-division comparison among a few voltages by using one comparator. CONSTITUTION: Prior to the selection of a signal source to be compared, e.g. signal source 111, the comparison threshold voltage of signal source 111 is applied to register 500 via bus 550 and the threshold-level voltage is set through D/A converter 400. Next, a control voltage is applied to input terminal 321 of electronic switch 301 and the voltage of signal source 111 is applied to comparator 101. At the point in time when an input voltage to comparator 101 is fixed and the output of comparator 101 is settled, a latch signal is supplied to terminal 215 of latch register 201. As a result, the comparison result of signal source 111 appears at output terminal 211. Switching comparisons of other signal sources 112 and 113 are made similarly. COPYRIGHT: (C)1980,JPO&Japio