摘要 |
<p>The circuit is intended to the detection of current modification signals of a needle transducer (Zs) connected to a constant direct voltage source and arranged in the injection device of an internal combustion engine. The circuit is capable of detecting very low signals particularly in vehicles where the high noise level conditions are prevailing. The transducer (Zs) is mounted at the output (4) of an adjustable direct voltage source (1) and is connected to a measurement resistance (RM) connected between the output (3) of a regulation amplifier (2) and the output of the direct voltage source (1). The output (3) of the regulating amplifier (2) is connected to the input of an alternating voltage amplifier (5) with pass-band. The output of the alternating voltage amplifier (5) is connected to the input of a Schmitt trigger (7) of which the output signal (UA) is representative of the variations of the sensor current (Is)</p> |