| 摘要 |
PURPOSE:To prevent the fluctuation of potential on a circuit earth line caused by a power noise current flowing in a body earth line, by separating the earth line of a noise filter from the circuit earth line and connecting each earth line to a car body individually. CONSTITUTION:Since the earth current based on the signal processing at a device electronic circuit 15 and the power supply noise current passing through an LC noise filter 2 flow to the earth line of separate systems, although an irregular potential difference is produced between an earth print pattern 12b exclusive for noise fieter and the car body 20 because of the voltage drop caused by the power supply noise current generated irregularly on a body earth line 14b exclusive for noise filter, the potential on an earth print pattern 12a being the earth line of the circuit 15 is not fluctuated because of the noise superimposed on the power supply line 1 even with a prolonged body earth line 14a, the LC noise filter 2 plays a sufficient role of noise rejection, allowing to actuate the circuit 15 surely. |
