A 79.2W 19.5kHz-BW 94.8dB-SNDR Fully Dynamic DT Σ ADC using CLS-Assisted FIA with Sampling Noise Cancellation

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

A fully-digital beat-frequency based ADC achieving 39dB SNDR for a 1.6mVpp input signal

A fully-digital VCO-based ADC featuring a novel beat frequency detection scheme is demonstrated in 65nm LP CMOS. The proposed beat frequency based ADC is unique compared to previous VCO-based ADCs in that it is highly effective in measuring extremely small changes (e.g., 0.01%) in the VCO frequency within a short sampling time (e.g., 100 VCO periods). Direct amplifier-less A-to-D conversion of ...

A 50MS/s 9.9mW pipelined ADC with 58dB SNDR in 0.18µm CMOS using capacitive charge-pumps

In the interest of extending battery life in mobile systems that use pipelined ADCs, several power-efficient pipelined ADCs have recently been proposed. The most promising topologies reported thus far are those that substitute the opamp, which is the largest consumer of power in pipelined ADCs, with alternative and more power-efficient circuits. However, opamp-less pipelined ADCs thus far eithe...