A current copying structure for current-mode monotonic digital-to-analog converters

摘要

This paper describes a 12-bit current mode digital to analog converter. Circuit topology uses two arrays of 64 equal current sources, each one generating both the current associated to six bits, corresponding to either MSB or LSB parts. The main novelty of that topology is the method used to limit the maximum current provided by the LSB block, which ensures a monotonic behavior of the system. The circuit has been designed and fabricated using a 0.35 /spl mu/m CMOS process and occupies an area of 0.17 mm/sup 2/.