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This paper presents a 2.3 GS/s 12-way time-interleaved pipelined-SAR ADC achieving 1.1 GHz input bandwidth with 47.4 dB signal-to-noise distortion ratio (SNDR). Here, we propose a hierarchical interleaving with passively shared sub-sampling front-end to eliminate the timing skews, thus avoiding the timing calibration for design simplicity as well as better area and power efficiency. To provide a fast signal transfer with good power efficiency to the sub-ADCs, the power and bandwidth trades off by using the passive sharing or active buffers are analyzed according to our developed mathematic model. The analysis is based on two scenarios: noise and matching limited sampling. Moreover, we propose a boosting-capacitor-sharing technique to enhance the compactness of the time-interleaved bootstrapped sampling front-end, which is particularly critical when omitted the time calibration in this design. Measurement results on a 65 nm CMOS prototype operated at 2.3 GS/s and 1.2 V supply show 31 mW total power consumption with a SNDR of 47.4 dB @Nyquist leading to a FOM of 69 fJ/conv.step. [ABSTRACT FROM AUTHOR]

This paper presents a 12b 180 MS/s 0.068 mm2 $2\times$ time-interleaved pipelined-SAR analog-to-digital conver-ter (ADC) with gain and offset calibrations fully embedded on-chip. The proposed binary-search gain calibration (BSGC) technique corrects the inter-stage gain error caused by the open-loop residue amplifier. The BSGC, fully integrated into the second-stage SAR ADC, contributes to a compact area. We improve the noise performance by implementing a merged-residue-DAC operation in the first-stage ADC. Also, we propose a dual-phase bootstrap technique to improve the sampling linearity in the partial interleaving architecture. The measurement results of the ADC prototype in 65 nm CMOS demonstrate the effectiveness of the proposed calibration through the enhancement of the signal to noise-and-distortion ratio from 51.5 to 60.9 dB at a Nyquist input, leading to a FoM@Nyq of 36.7 fJ/conversion-step. [ABSTRACT FROM AUTHOR]