A complete single-supply microprocessor-compatible 8-bit DAC

A functionally complete, microprocessor-compatible digital-to-analog converter which operates on a single +5 V supply is described. This monolithic bipolar chip is fabricated using a linear compatible I/SUP 2/L process and contains both a precision reference and a voltage output buffer, along with the DAC and input logic. Laser wafer trimming of on-chip thin-film resistors is used to guarantee output response linearity as well as the absolute calibration of end points. The new circuit techniques which were developed to allow low-voltage single-supply operation with no sacrifice in performance are described and analyzed in detail.