| 摘要 |
PROBLEM TO BE SOLVED: To output a signal via a transmission path in a state where attenuation is reduced, while high frequency noise is eliminated.SOLUTION: A current sensor includes: a coil 5 wound around a magnetic core 2 inserted with an electric path 21 to be measured in an inner part and connected to a ground G side at one end 5a and outputting from the other end a current I2 of the current value according to the current value of a current I1 to be measured and flowing in the electric path 21 to be measured; a constant impedance filter 7 in which an input terminal 7a is connected to the other end 5b of the coil 5 and the frequency region of a current I2 inputted from an input terminal 7a is limited to a desired frequency region and is outputted from an output terminal 7b; a transmission path 8 in which one end 8a is directly connected to the output terminal 7b of the filter 7; and a terminal resistor 9 connected between the other end 8b of the transmission path 8 and the ground G and converting the current I2 flowing via the transmission path 8 into a detecting voltage V2. The filter 7 has impedance viewing the terminal resistor 9 side from the input terminal 7a regulated to the same value as a characteristic impedance of the transmission path 8.SELECTED DRAWING: Figure 1 |
