| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a gas concentration detection system which does not output a gas concentration signal on which a noise component is superposed to a signal acquisition means even when a signal holding means holding a voltage of a terminal connected to one electrode of an oxygen concentration measurement cell is brought into a releasing state after the element resistance of the cell is detected. <P>SOLUTION: The gas concentration detection system 1 includes both a first sample holding circuit 81 for holding a voltage of an immediately preceding terminal Vs+1 (a second terminal Vs+) when an element resistance of the oxygen concentration measurement cell 24 is to be detected and a second sample holding circuit 83 for holding an immediately preceding gas concentration signals Vip outputted from a first differential amplifier 54. When the voltage holding state of both circuits 81 and 83 is to be released, the timing of changing over a switch SW3 of the second sample holding circuit 83 between ON or OFF to release the voltage holding state is set later than the timing of changing over a switch SW9 of the first sample holding circuit 81 from Off to ON to release the voltage holding state. <P>COPYRIGHT: (C)2007,JPO&INPIT |
