Abstract: A wide range oxygen sensor comprising a first oxygen pump cell, the first pump cell comprising: a first and a second electrode, with a first communication zone therebetween, the first electrode being exposed to exhaust gas, the second electrode being exposed to a heat source; and wherein at least one element of said first pump cell incorporates a gas-diffusion limiting characteristic; a second oxygen pump cell, operating at opposite polarity from said first oxygen pump cell, electrically isolated from said first oxygen pump cell, and disposed within a sensor substrate, the second cell comprising: a third and a fourth electrode, with a second communication zone therebetween, the third electrode being exposed to exhaust gas, the fourth electrode being exposed to a heat source; and wherein at least one element of said second pump cell incorporates a gas-diffusion limiting characteristic; at least one heating element for providing heat to said second electrode and said fourth electrode; and an electrical circuit

Abstract: A gas sensor for sensing NOx having electrochemical cells wherein dielectric material surrounds electrolytes except where electrodes are attached. Thereby, the exhaust gas is effectively prevented from contacting the electrolytes of the sensor's electrochemical cells. With the use of this technique, signal cross talk is minimized while enhancing NOx sensing sensitivity. Further, the total number electrodes needed are reduced which allows for more complex sensors structures.

Abstract: A heater for a gas sensor has a first thermistor element and a second thermistor element arranged in an electrically parallel configuration. Each thermistor element may be deposited onto a substrate such that the first thermistor element extends about a perimeter of the substrate and the second thermistor element extends across a portion of the substrate intermediate the perimeter of the substrate. The thermistor elements are preferably fabricated of materials having differing thermal coefficients of resistivity. A method of heating the gas sensor includes disposing the two thermistor elements in an electrically parallel configuration over a surface of the substrate and passing an electric current through the elements.

Abstract: A heater pattern for a heater of a gas sensor in which a temperature profile is manipulated utilizes a thermistor element arranged in an electrically serial configuration and disposed on a substrate. The thermistor element is arranged so as to define an edge pattern extending about a perimeter of the substrate and a center pattern serially connected to the edge pattern. The center pattern extends over a portion of the substrate that is intermediate the perimeter of the substrate. In a preferred embodiment, the thermistor element is screen printed onto the substrate to a thickness of about 5 microns to about 50 microns, and preferably to a thickness of about 10 microns to about 40 microns. The edge and center patterns are furthermore preferably formed of materials having differing coefficients of thermal resistivity, e.g., platinum and platinum/palladium blends.

Abstract: A gas sensor for sensing NOx having electrochemical cells wherein dielectric material surrounds electrolytes except where electrodes are attached. Thereby, the exhaust gas is effectively prevented from contacting the electrolytes of the sensor's electrochemical cells. With the use of this technique, signal cross talk is minimized while enhancing NOx sensing sensitivity. Further, the total number electrodes needed are reduced which allows for more complex sensors structures.

Abstract: A heater for a gas sensor has a first thermistor element and a second thermistor element arranged in an electrically parallel configuration. Each thermistor element may be deposited onto a substrate such that the first thermistor element extends about a perimeter of the substrate and the second thermistor element extends across a portion of the substrate intermediate the perimeter of the substrate. The thermistor elements are preferably fabricated of materials having differing thermal coefficients of resistivity. A method of heating the gas sensor includes disposing the two thermistor elements in an electrically parallel configuration over a surface of the substrate and passing an electric current through the elements.

Abstract: A heater pattern for a heater of a gas sensor in which a temperature profile is manipulated utilizes a thermistor element arranged in an electrically serial configuration and disposed on a substrate. The thermistor element is arranged so as to define an edge pattern extending about a perimeter of the substrate and a center pattern serially connected to the edge pattern. The center pattern extends over a portion of the substrate that is intermediate the perimeter of the substrate. In a preferred embodiment, the thermistor element is screen printed onto the substrate to a thickness of about 5 microns to about 50 microns, and preferably to a thickness of about 10 microns to about 40 microns. The edge and center patterns are furthermore preferably formed of materials having differing coefficients of thermal resistivity, e.g., platinum and platinum/palladium blends.

Abstract: A heater for a gas sensor has a first thermistor element and a second thermistor element arranged in an electrically parallel configuration. Each thermistor element may be deposited onto a substrate such that the first thermistor element extends about a perimeter of the substrate and the second thermistor element extends across a portion of the substrate intermediate the perimeter of the substrate. The thermistor elements are preferably fabricated of materials having differing thermal coefficients of resistivity. A method of heating the gas sensor includes disposing the two thermistor elements in an electrically parallel configuration over a surface of the substrate and passing an electric current through the elements.