| 摘要 |
<p>PURPOSE:To obtain a sensor which operates stably by avoiding poor operation due to variations in offset voltage at the applications of a power source. CONSTITUTION:This sensor 10 contains a bridge circuit 20. The bridge circuit 20 is made up of a temperature sensor 12 for a heater, a temperature sensor 14 for temperature compensation and two resistances 16 and 18. An output terminal on the side of the temperature sensor 12 for the heater of the bridge circuit 20 is connected to an inversion input terminal 22a of an operational amplifier 22 and an output terminal of the temperature sensor 14 for temperature compensation of the bridge circuit 20 is connected to a non- inversion input terminal 22b of the operational amplifier 22. The base of a transistor 26 is connected to an output terminal 22c of the operational amplifier 22 to feed back an output from the emitter of the transistor 26 to the bridge circuit 20. Moreover, a power source VCC is connected to the non-inversion input terminal 22b of the operational amplifier 22 through a capacitor 24 for compensation or a bias resistor.</p> |
