Analysis of a Current Mode MOST-only D-A Converter

The subject of this paper is a MOST-only current mode D-A converter. Its topology resembles that of an R-2R ladder. The MOSTs are used to implement both weight factors and switches. Its operation is based on a current division principle [1]. Error sources are identified and analyzed resulting in a fairly simple method to predict achievable performance. Analysis and measurements show 9-bit resolution.