A 10MHz BW 78dB DR CT ΣΔ modulator with novel switched high linearity VCO-based quantizer

A continuous-time VCO-assisted VCO-based ΣΔ modulator with 76.6dB SNDR and 10MHz BW

In this paper, a new VCO-assisted VCO-based sigmadelta (ΣΔ) modulator is proposed to improve the linearity of the VCO-based quantizer. The assistant network in the digital feedforward path reduces the input swing of the VCO-based quantizer in the main path, and then adds it together through the digital cancellation path to keep the same signal before and after quantization. Moreover, the merit ...

A DT 0-2 MASH ΣΔ modulator with VCO-based quantizer for enhanced linearity

This paper presents a new structure of the discrete time 0-2 MASH sigma-delta modulator implemented with VCObased quantizer in the second stage. The proposed scheme enhances the linearity of the VCO based quantizer, meanwhile it takes advantage of the intrinsic DEM function and first order noise shaping in the second stage. Besides, the matching requirement is relaxed and the digital canceling ...

A 0.13[mu]m CMOS 78dB SNDR 87mW 20MHz BW CT [Delta Sigma] ADC with VCO-based integrator and quantizer

A 174.3dB FoM VCO-based CT ΔΣ modulator with a fully digital phase extended quantizer and tri-level resistor DAC in 130nm CMOS

This paper presents a high dynamic range (DR), power efficient VCO-based continuous time ΔΣ modulator (CTDSM). It introduces a simple, robust and low power fully digital phase extended quantizer (PEQ) that doubles the VCO quantizer resolution compared to conventional XOR-based phase detector with minimum overhead. A tri-level resistor DAC is also introduced as complementary to the new quantizer...

A 0.13µm CMOS 78dB SNDR 87mW 20MHz BW CT ΔΣ ADC with VCO-based integrator and quantizer

Voltage-controlled oscillator (VCO) based ADCs have become a topic of great interest due to the unique and attractive signal-processing properties they offer in the design of oversampling converters. Assuming a ring-oscillator structure, the outputs of a VCO toggle between two discrete levels (VDD and GND) like a CMOS digital gate, enabling simple multibit quantization using Dflip-flops. Since ...