Patent ID: 7193406

Claim:
A data transmitting and receiving apparatus, in a sensor system which has a sensor unit that includes a sensor element and a memory storing data regarding said sensor element and the data transmitting and receiving apparatus to which a detected signal from said sensor element is input and which transmits data to and receives data from said memory, and in which said input of the detected signal and said data transmission and reception is performed by sharing a single signal line, comprising: a first logic inversion element and a second logic inversion element connected in parallel in the direction opposite to each other and connected in series to said single signal line; and a level limiter connected in series at least to either the signal output side of said first logic inversion element or the signal input side of said second logic inversion element, wherein a signal output from said first logic inversion element is attenuated by said level limiter and is blocked by said second logic inversion element.