Patent ID: 6429719
Filing Date: 2002-08-06
Classification: G01L

Abstract:
A signal processing circuit for a charge generation detection device, comprising a charge-voltage conversion circuit for converting a charge generated in the charge generation detection device to a voltage, the charge-voltage conversion circuit including:a first capacitor for storing the charge generated in the charge generation detection device; an operational amplifier, an output of the operational amplifier being connected to an input of the operational amplifier via the first capacitor so as to form a feed-back loop; and a first switch connected in parallel with the first capacitor for discharging the charge stored in the first capacitor, wherein the first switch includes a first transistor for generating a first clock feed-through and a second transistor for generating a second clock feed-through, a first source electrode and a first drain electrode of the first transistor are connected in parallel with the first capacitor, and a second source electrode and a second drain electrode of the second transistor are connected in parallel with the first capacitor so that at least a portion of the first clock feed-through is cancelled by the second clock feed-through, the signal processing circuit further comprising a feed-back circuit for feeding an output of the charge-voltage conversion circuit back to an input of the charge-voltage conversion circuit, wherein the charge-voltage conversion circuit and the feed-back circuit has a delta/sigma modulation function.