High Speed DAC architectures

What architecture do high speed DAC products from ADI use? What is Differential Quad Switching and its advantages?

  • The high speed DAC products from Analog Devices use the Switched Current Architecture. DACs with this architecture sometimes are also called current-steering DACs. The analog output of such a DAC is a current whose magnitude is proportional to the digital input code. Typically, the output is a differential signal. The sum of the two ends of the differential output is a constant value, which is nominally 20mA.

    Differential Quad Switching is an ADI proprietary DAC architecture. The DAC core switches twice as fast as the input DAC clock rate. Therefore it eliminates the data-dependant nonlinearity, which in turn, delivers better DAC AC performance such as harmonic and inter-modulation distortion performance.