Analog to digital converter including differential vco

Abstract

An analog to digital converter is provided. The analog to digital converter includes: an arithmetic operator combining an analog input signal with a feedback signal; a loop filter filtering an output signal of the arithmetic operator; a quantizer quantizing an output signal of the loop filter to output a digital signal; and a feedback converting the digital signal to output a feedback signal, in which the quantizer includes: a plurality of VCOs each receiving a positive output signal and a negative output signal of the loop filter and outputting VCO signals; a plurality of samplers receiving the VCO signals output from the plurality of VCOs, respectively and outputting sampled signals; and a phase detector detecting a phase difference in the sampled signals output from the plurality of samplers, respectively, to detect a phase difference in two VCO signals output from the plurality of VCOs, respectively.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority from Korean Patent Application No. 10-2016-0033362 filed on Mar. 21, 2016 and Korean Patent Application No. 10-2017-0027481 filed on Mar. 3, 2017 in the Korean Intellectual Property Office the disclosure of which is incorporated herein by reference in its entirety.BACKGROUND OF THE INVENTION[0002]Field of the Invention[0003]Apparatuses and methods consistent with the present disclosure relate to an analog to digital converter including a differential VCO, and more particularly, to an analog to digital converter including a differential VCO that uses a phase domain and reduces an area and power consumption.[0004]Description of the Related Art[0005]Recently, there is an increasing demand for multi-mode or multi-band in wireless communication. To this end, researches on a digital RF front-end are actively under way. In particular, to support the multi-mode or the multi-band, we are trying to reduce a use of a...

AI Technical Summary

Benefits of technology

The present invention provides an analog to digital converter that includes a differential VCO. This converter can increase the range and dynamic range of the output signal without requiring an extra circuit and without being affected by the reference frequency. It is also more efficient in terms of area, power consumption, and yield.

Problems solved by technology

However, since a V-to-frequency transfer function of the VCO is operated non-linearly, there is a disadvantage in that a harmonic distortion occurs in an output signal.

The DC offset limits an output range of a feedback digital to analog converter and may lead to a reduction in a dynamic range, which limits the performance of the analog to digital converter.

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