Design Of Very Highfrequency Multirate Switchedcapacitor Circuits: Extending The Boundaries Of Cmos Analog Frontend Filtering

Design of Very HighFrequency Multirate SwitchedCapacitor Circuits presents the theory and the corresponding CMOS implementation of the novel multirate sampleddata analog interpolation technique which has its great potential on very highfrequency analog frondend filtering due to its inherent dual advantage of reducing the speed of dataconverters and DSP core together with the specification relaxation of the post continuoustime filtering. This technique completely eliminates the traditional phenomenon of sampledandhold frequencyshaping at the lower input sampling rate. Also, in order to tackle physical IC imperfections at very high frequency, the stateoftheart circuit design and layout techniques for highspeed SwitchedCapacitor (SC) circuits are comprehensively discussed:Optimum circuit architecture tradeoff analysisSimple speed and power tradeoff analysis of active elementsHighorder filtering response accuracy with respect to capacitorratio mismatchesTimeinterleaved effect with respect to gain and offset mismatchTimeinterleaved effect with respect to timingskew and random jitter with nonuniformly holdingStage noise analysis and allocation schemeSubstrate and supply noise reductionGainand offsetcompensation techniquesHighbandwidth lowpower amplifier design and layoutVery low timingskew multiphase generationTwo tailormade optimum design examples in CMOS are presented. The first one achieves a 3stage 8fold SC interpolating filter with 5.5MHz bandwidth and 108MHz output sampling rate for a NTSC/PAL CCIR 601 digital video at 3 V. Another is a 15tap 57MHz SC FIR bandpass interpolating filter with 4fold sampling rate increase to 320MHz and the firsttime embedded frequency band uptranslation for DDFS system at 2.5V. The corresponding chip prototype achieves so far the highest operating frequency, highest filter order and highest center frequency with highestdynamic range under the lowest supply voltage when compared to the previously reported highfrequency SC filters in CMOS.