the frequency content i e radio frequency range of the output analog waveform from any dac is dependent on the speed or u201c sampling rate u201d of the dac the u201c sampling u201d rate is the interval that measurements i e samples of a source are taken according to the well known nyquist sampling theorem an analog waveform may be reconstructed from samples taken at equal time intervals but the sampling rate must be equal to or greater than twice the highest frequency component in the analog waveform that is if the highest frequency component in an analog waveform is 5 gigahertz ghz then the sampling rate must be at least 10 ghz for example one type of communication system transmits at the 5 ghz radio frequency therefore a dac would need a sampling rate of at least 10 ghz to directly synthesize a 5 ghz signal another important performance parameter of a dac is its u201c dynamic range u201d the dynamic range of a signal generated by a dac is a function of the number of digital bits the dac can process for example a 12 giga sample 6 bit dac is capable of generating a signal that has a dynamic range of 6 bits and a frequency range from dc zero hertz up to 6 ghz u00bd of 12 ghz one feature of the dac disclosed herein is that it can generate or synthesize communications waveforms at up to 10 ghz thus capable of sampling at 20 ghz it will be appreciated that the features and functionalities disclosed herein may be employed.