Device for the multiplicative correction of an electric measurement signal

摘要

The invention relates to a device for the multiplicative correction of a slowly varying electric measurement signal to be supplied to an analog/digital converter from a sensor, particularly of the measurement signal of an airflow meter located in the air intake duct of an internal combustion engine, in dependence on positive and negative deviations in time of an electric reference signal, which is used as reference quantity for the analog/digital converter, from its nominal value. This device is characterised by a sawtooth generator for generating a sawtooth voltage, the mean value of which corresponds to the nominal voltage value of the reference signal and the peak-to-peak deviation of which corresponds to the maximum peak-to-peak deviation of the reference signal, by a comparator for continuously comparing the reference signal with the sawtooth voltage for generating a control pulse sequence, the duty ratio of which ranges from 0% to 100% within the maximum peak-to-peak deviation of the reference signal, by a voltage divider, fed by the uncorrected measurement signal, with an on/off switch cycled by the control pulse sequence of the comparator and with a voltage divider tap at which the measurement signal is present as a modified signal alternately unchanged and slightly reduced in accordance with the voltage divider ratio in dependence on the duty ratio of the control pulse sequence, the temporal proportion of the measurement signal reduction compared with the unchanged... Original abstract incomplete.