| 摘要 |
PURPOSE:To transduce pressure, etc., into a voltage through simple, small-sized constitution which requires no bridge circuit by transducing the amount of variation in differential resistance into the voltage by an operational amplifier. CONSTITUTION:Resistances 23 and 24 which have an initial resistance value R and resistance value variation DELTAR with pressure, etc., are driven by voltage sources 25 and 26 which supply voltages E and -E respectively to perform differential operation. The sum output of those resistances 23 and 24 is applied to the inverted input terminal of the operational amplifier 21 which connects with a feedback resistance 22 with a resistance RL and has the uninverted input terminal is grounded. Then, the algebraic sum of a current flowing to the inverted input terminal is zero, so the output voltage V0 of the amplifier 28 is based upon an equation I ; and the resistance value corresponding to the pressure, etc., is transduced into a voltage by the simple constitution which requires no bridge circuit; etc., and the sensitivity is adjusted freely according to a selected Rf/R. |
