| 摘要 |
PURPOSE:To remove the factor to be a cause to error, by fixing one of the output terminals of the two bridge circuits at a suitable level to constitute the output of the bridge circuits as an unbalanced output and amplifying the output of another terminal at the unbalanced amplifier. CONSTITUTION:The Zener diode 7 is connected between the input terminals (a) and (c) of the bridge circuit 5 to keep the terminals (a) and (c) at a constant voltage, and no terminals (a) and (c) are grounded. The output terminal (d) is connected with the inverting input terminal of the operational amplifier 31 and the noninverting terminal is grounded. The output terminal of the operational amplifier 31 is connected to the input terminal (c) of the bridge circuit 5 so that the resistor 3 of one side of the bridge circuit 5 can be inserted to the feedback loop. The feedback loop fixes the inverting input terminal of the operational amplifier 31, i.e. the terminal (d) at almost zero potential. The current flowing to the resistor 4 is not branched to the operational amplifier 31 but through the resistor 3. |
