[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.5573/IEIESPC.2015.4.3.145

A Multi-bit VCO-based Linear Quantizer with Frequency-to-current Feedback using a Switched-capacitor Structure

Park, Sangyong (School of Electrical Engineering, Chung-Ang University)
Ryu, Hyuk (School of Electrical Engineering, Chung-Ang University)
Sung, Eun-Taek (School of Electrical Engineering, Chung-Ang University)
Baek, Donghyun (School of Electrical Engineering, Chung-Ang University)

Publication Information

IEIE Transactions on Smart Processing and Computing / v.4, no.3, 2015 , pp. 145-148 More about this Journal

Abstract

In this letter, we present a new linearization method for a voltage controlled oscillator (VCO)-based quantizer in an analog-to-digital converter (ADC). The nonlinearity of the VCO generates unwanted harmonic spurs and reduces the signal-to-noise and distortion ratio (SNDR) of the VCO-based quantizer. This letter suggests a frequency-to-current feedback method to effectively suppress harmonic distortion. The proposed method decreases the harmonic spurs by more than 53 dB. And a VCO-based quantizer employing the proposed linearization method achieves a high SNDR of 74.1 dB.

Keywords

VCO; Quantizer; Low harmonic distortion; Frequency-to-current feedback;

Citations & Related Records

Reference

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