| CPC H03M 1/0609 (2013.01) [G01N 27/122 (2013.01)] | 7 Claims |
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1. A method for the precise acquisition of a signal of a sensor by an evaluation and control unit electrically connected to the sensor, the evaluation and control unit having a multiplexer at whose inputs there is at least one reference voltage whose voltage value is known, a ground potential of the reference voltage, a measurement signal of an exhaust gas sensor, and a ground potential of the measurement signal, a computer being connected downstream from the multiplexer via a transmission path and via an analog to digital converter (ADC) that converts a voltage between two inputs of the ADC into a digital value, the method comprising the following steps:
carrying out a plurality of individual measurements, wherein in each of the individual measurements, switching states of the multiplexer are modified, and in each of the individual measurements which digital values are subsequently acquired at an output of the ADC; and
calculating, by the computer, a corrected measurement value, corrected with regard to offset and gain, from the digital values;
wherein the digital values are each acquired before two levels at the inputs of the ADC have settled, or the analog to digital conversion by the ADC is begun before the two levels at the inputs of the ADC have settled,
wherein the two levels at the inputs of the ADC are not considered settled until the output of the ADC achieves at least 86% of a change according to a stationary solution with the modified switching states of the multiplexer.
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