AUTOMATIC COMPENSATION CIRCUIT

PURPOSE:To accurately and automatically compensate the characteristic change of the input signal based on external change, by preliminarily storing the correction data to the variation in the input signal generated by the external change and compensating the input signal on the basis of said correction data. CONSTITUTION:The true value data from a data generator 21 is supplied to a comparator 22 along with the detection data of input Sin to be measured from an adder 18 and the comparing result of both data is led out to a correction value generating counter 23. The clock signal from a clock generator 24 is counted until the detection data coincides with the true value data and the count result is led out to RAM 26 as correction data through a gate circuit 25. The reading/writing address data to RAM 26 is obtained from the output data of a temp. detector 27 detecting the change in the circumferential temp. of machinery. The detection signal of the detector 27 is read through an A/D converter 29 to be supplied to the adder 18 as an address signal and the correction data corresponding to circumferential temp. is read to be sent the adder 18 and added to detection data to accurately compensate the variation due to temp. change.