DEVICE FOR DIGITISING AN ANALOG VOLTAGE

摘要

A device for digitising an analog voltage has a first analog/digital converter channel (5, 1) to convert the analog input voltage into a roughly quantified digital value. A digital/analog converter consisting of an adjustable pulse-width generator (18) with a downstream low-pass filter (30) converts the digital value obtained back into an analog voltage. In addition, the device has a differential amplifier (34) which forms and amplifies the difference between the analog input voltage Ue and the reconverted analog voltage. The amplified differential voltage (38) obtained is converted into a finely quantified digital value in a second analog/digital converter channel (40, 1). The first and second analog/digital converter channels (5, 40) are preferably formed by an analog/digital converter (1) with an upstream multiplexer (3). The pulse width generator (18) with its downstream low-pass filter (30) makes for highly accurate conversion. The advantage of the device lies in its very simple, economical and accurate analog/digital conversion.