A low-cost dual 16-bit DAC for digital audio equipment

Describes a dual 16-bit DAC which has THD of -75 dB and a dynamic range of 95 dB. It uses the symmetrical offset principle to achieve a (THD+noise)/S curve which closely approaches the ideal for small signals. No external components or adjustments are required. This integrated dual 16-bit digital DAC can be for use in audio equipment such a CD players and digital tape recorders. The flexible format for the input data allows simple interfacing with signal processing ICs such as interpolation filters, error correction circuits and audio signal processors. The high input bit-rate and fast-settling output facilitate application of the converter, together with simple external active analog filters (low-order, linear-phase filters), in oversampling systems. An adjustable current is added to the output currents to bias the external op-amps for maximum dynamic range. The converter is fabricated in a standard bipolar process, occupies a chip area of 3.5*3.1 mm/sup 2/ and comes in an 8-pin DIL package.<>