Limiting-current type air–fuel ratio sensor using porous zirconia layer without inner gas chambers: proposal for a quick-startup sensor

17 Interface Circuitry and Microsystems

“…Systems for engine emission and combustion control, based on microsensors, are also being developed. [12][13][14][15][16][17] They combine physical and chemical sensors that measure the state of the engine; for example, pressure in the cylinder, oxygen content in the exhaust gases, and engine rotation speed. These data are processed and used to regulate spark ignition and fuel injection, to optimize the performance of the engine in terms of fuel consumption and pollution.…”

“…Usually, it consists of a "sinc" filter with a transfer function (15) INTERFACE CIRCUITRY AND MICROSYSTEMS, MALCOVATI, MALOBERTI 925 The most interesting oversampled A/D converters for sensor applications are first-and second-order ΣΔ modulators. Due to severe stability problems, which degrade the performance, reliability, and robustness of third-order or higher order modulators, their use in microsensor interfaces is generally impractical.…”

Oxygen detection using junctions based on thin films of yttria-stabilized zirconia doped with platinum nanoparticles and pure yttria-stabilized zirconia

“…Its sensing area of 380 m × 240 m represents a substantial reduction in size from current sensors. The sensor response to oxygen begins from 450 • C and reaches its operation range between 560 and 611 • C. Other kind of structure is proposed in [12] for a quick-start-up air-fuel ratio sensor. It is a compact sensing part which is directly stacked on a heater, where porous and dense zirconia layers are combined without inner gas chamber.…”

Preparation and characterization of zirconia oxygen sensors

“…Many structures and principles of zirconia oxygen sensors have been proposed for the measurement of exhaust gas [7][8][9][10][11][12] . However, because of their reliability or other problems, only is the application of thimbletype oxygen sensors that have dominated the market of oxygen sensor most successful.…”