Integrated weighted current digital to analog converter

Abstract From the Canadian patent

A weighted current digital to analog converter (DAC) translates digital bits to corresponding analog signals by a suitably operated transfer circuit of (1) multipled parallel current sources for more significant bits and (2) binary weighted current sources for lesser significant bits. The number of resistors and the ratio of adjacent resistors is reduced in the transfer circuit relative to a ladder type DAC. Power saving and linearity are improved by the reduced number and ratio of adjacent resistors. The transfer circuit facilitates fabrication of the DAC in a semiconductor. Temperature stability is improved by proper location of the current sources in the semiconductor.