Wide-band Direct Sampling Mixer with complex-pole synthesis

When we utilize Direct Sampling Mixer (DSM) for wide-band wireless standard, it is preferable to attenuate undesired adjacent blockers before ADC. This paper proposes a novel direct sampling mixer (DSM) with much more flexible complex-pole placement, achieving a much wider pass-band characteristic than that of basic DSM filter with real poles. Although complex-pole technique has been reported so far, the conventional method has a limitation with regard to complex-pole position. We eliminated the limitation by introducing charge pumps and voltage followers. We used 2 indices, DU ratio and in-band deviation, to evaluate the wide-band performance.