A 79.5dB-SNDR Pipelined-SAR ADC with a Linearity-Shifting 32× Dynamic Amplifier and Mounted-Over-Die Bypass Capacitors

This paper presents a $32\times $ low-noise dynamic amplifier (DA) with a linearity-shifting technique, facilitating a 15b pipelined-SAR ADC with 80 dB $SNR_{\text{@}DC}$. The linearity-shifted DA decouples the fundamental conflict between the noise and linearity in conventional DAs, rending a THD below -60dB at $0.8\mathrm{~V}_{\mathrm{pp,diff}}$ output swing. Moreover, the reference voltages are stabilized by the cost-effective mounted-over-die bypass capacitors. The 60MS/s ADC achieves 95.8dB and $87.3\mathrm{~dB}$ SFDR with a DC and Nyquist input, respectively, and an input noise density of $10.2\mathrm{nV}/\sqrt{\mathrm{Hz}}$.