| 摘要 |
<p>A method of and apparatus for detecting if a MOS gas sensor (400) has been poisoned, the sensor having a sensor element for sensing a target gas and having a heater configured to heat the sensor element in response to a voltage being applied to the heater. The heater having an operating temperature which is selectively maintained by applying a first voltage thereto. The method includes reducing the voltage from the first voltage and sensing a change in resistance of the sensor element which is responsive to the reduction of the voltage from the first voltage and comparing the sensed changes with expected changes. The apparatus includes cir cuitry (402) configured to reduce the voltage from the first voltage and the same or different circuitry senses a change in resis tance of the sensor element which is responsive to the reduction of the voltage from the first voltage and compares the sensed changes with expected changes.</p> |
