A Second Order Passive Noise-Shaping SAR ADC based on FVF Dynamic Buffer
A high precision second order passive noise shaping successive approximation analog-to-digital converter(NS SAR ADC)is proposed in this paper.Firstly,a technique for kT/C noise cancellation via a dynamic floating reverse amplifier(FIA)was used,followed by a custom capacitor with a differential structure to achieve a smaller capacitor array area while suppressing sampling thermal noise.Finally,the residual voltage is extracted by using the flipped voltage follower(FVF)structure as a dynamic buffer,and the passive summation is realized by the capacitor stacking operation,and the comparator noise and quantization noise are shaped in the second order.This design is realized by 0.18 µ m process.The simulation results show that the signal-to-noise ratio(SNDR)is 88.57dB and the spury-free dynamic range(SFDR)is 99.09dB at 1.8V supply voltage,8x oversampling rate and 2MS/s sampling frequency.Power consumption is only 302 µ W.
NETL
NSTL
万方数据
维普
