一种级间运放共享的MASH结构Σ-Δ调制器

A MASH Structure Interstage Op-Amp SharingΣ-ΔModulator

基于55 nm CMOS工艺,设计了一种级间运放共享的级联噪声整形(MASH)结构Σ-Δ调制器。采用2-2 MASH结构对调制器参数进行了设计。对经典结构的开关电容积分器进行了改进,并应用到调制器电路的设计中,实现了两级调制器之间的运放共享,在达到高精度的同时减少了运放的数量,显著降低了MASH结构调制器的功耗。仿真结果表明,在3.3 V电源电压下,调制器信噪失真比为111.7 dB,无杂散动态范围为113.6 dB,整体功耗为16.84 mW。

A multi-stage noise-shaping(MASH)structure interstage op-amp sharingΣ-Δmodulator was designed in a 55 nm CMOS process.A 2-2 MASH structure was used to design the modulator parameters.An improvement had been made to the classical switched-capacitor integrator and applied to the design of the modulator circuit,realizing the sharing of op-amps between the two stages of the modulator,reducing the number of op-amps while achieving high precision,and significantly decreasing the power consumption of the MASH structure modulator.Simulation results show that at a supply voltage of 3.3 V,the modulator have a signal-to-noise-and-distortion ratio of 111.7 dB,a spurious-free dynamic range of 113.6 dB,and a total power consumption of 16.84 mW.