| 摘要 |
PROBLEM TO BE SOLVED: To provide a detection system which requires no wire for use in grounding of a signal processing circuit and allows the noise in an output signal from the signal processing circuit to be reduced.SOLUTION: An implementation substrate 210 comprises an integration circuit 213 which integrates a charge signal Qi from a piezoelectric device 10 for conversion to a voltage signal, an amplification circuit 214 which amplifies the voltage signal, and a power source circuit 216 which supplies an internal power source voltage Vr to the integration circuit 213 and the amplification circuit 214. To the implementation substrate 210, the charge signal Qi is inputted from an input signal terminal 211a, and an external power source voltage Vc is inputted from a first cable through a power source terminal 211c. An external output voltage Vo is outputted from an external signal terminal 211d through a second cable. The power source circuit 216 creates the internal power source voltage Vr with reference to the external power source voltage Vc supplied from outside, without reference to the ground potential at the implementation substrate 210. |
