INPUT DEVICE FOR ANALOG INPUT SIGNAL

摘要

PROBLEM TO BE SOLVED: To allow the input device to cope with many more multi-point and multi-kind inputs in addition to the enhanced measurement accuracy by setting each digital value after A/D conversion to have an upper/lower limit full scale in the adjustment mode and obtaining a digital value by means of interpolation or extrapolation from both the full scale values in the measurement mode so as to eliminate the need for external adjustment. SOLUTION: The analog input device 101 receives analog input signals (0)...(n), an input signal 112 among them selected by a multiplexer 111 is amplified by an amplifier circuit 113, and the amplified signal is converted into a digital signal 115 by an A/D converter 114. The digital signal 115 is stored in a memory 118 as a measured value 117 for each measurement point under the control of a CPU 116 and also sent to a host device 119. Furthermore, a changeover section 130 that selects the adjustment mode or the measurement mode employs an adjustment mode/measurement mode changeover switch in the inside to select any mode.