| 摘要 |
PROBLEM TO BE SOLVED: To provide a sensor signal detection circuit capable of appropriately detecting a sensor signal using a simple configuration.SOLUTION: The present invention pertains specifically to a contact detection circuit 9 for detecting a change in a direct-current sensor signal S based on a change in the physical quantity to be detected. The contact detection circuit 9 comprises: a reference signal generation circuit 22 for generating a reference signal K(S0+S1) from the direct-current sensor signal S; a trigger signal output circuit 24 for comparing the direct-current sensor signal S and the reference signal, and outputting a trigger signal TG on the basis of the result of the comparison; and a sample-and-hold circuit 23 which, when the trigger signal TG is outputted, holds the reference signal at start of the outputting of the trigger signal TG, and which, while the trigger signal TG is being outputted, outputs the reference signal that is held to the trigger signal output circuit 24. The trigger signal output circuit 24 uses, for comparison with the direct-current sensor signal S, the reference signal that is outputted from the sample-and-hold circuit 23 when the trigger signal TG is being outputted. |
