| 摘要 |
PURPOSE:To simplify constitution, by subjecting the signal from plural thermoresistances to the operation processing together with signals from sensors for ambient temperature measurement and reference voltage measurement through the front end part. CONSTITUTION:Though resistance value (r) of the thermoresistor for temperature T is expressed by r=ro (1+alphaT+betaT<2>), measure temperature T is changed to T=TA+Zsin(2pi.TA/600), TA=f(r)=G(V, R, vdelta, vr)) because error is large in the high temperature side specially, and a current is flowed from reference power source V to thermoresistance (r) through reference resistance R, and signals of overall voltage drop components vr including line resistances a-a' and c-c' and voltage drop component vdelta dependent upon only line resistance c-c' are measured at very one measure point. As a result, the temperature can be measured dependently upon the thermoresistance with a high precision without the complicated bridge circuit, the linearize circuit, and so on by simple hardware, the general microcomputer, and so on. |
