Diagnostic apparatus for digital-to-analog converters

Abstract From the Canadian patent

An apparatus for diagnosing a plurality of digital to-analog converters simultaneously is provided. Digital signal generation means applies digital signals to the plurality of digital-to-analog converters, and the digital signals are changed in sequence so that the analog outputs from the converters are changed symmetrically with respect to a first predetermined value. The analog otuputs from the converters are combined by a resistor network, and the combined output is compared with a second predetermined value by a comparator. If the comparator's output is kept to a predetermined level regardless of changing the digital signals, the digital-to-analog converters are judged that they operate …