The electronic circuit (fig 1) has a phase shift oscillator with a transducer sensor as a component. The transducer sensor is a gas sensitive substance such as a semiconductor polymer which changes its electrical property in accordance with adsorption or desorption of a gas. The circuit is used as a gas sensor. The adsorption or desorption of gas changes the phase of the oscillator for a given frequency.The frequency can be varied and the frequency for zero phase shifted under gas adsorption or desorption conditions, or a quantity functionally related to it, measured. The value of this frequency or quantity functionally related to is used as an indication of the presence of a particular gas. The circuit contains several semiconducting polymer components.USE - Relates to electronic circuits for gas sensor devices.ADVANTAGE - Signal produced is near digital allowing for ready integration with digital processing techniques.
|Patent number||WO9838502-A; WO9838502-A1|
|Publication status||Published - 1998|