TY - GEN
T1 - A current-mode VCO-based amplifier-less 2nd-order ΔΣ modulator with over 85dB SNDR
AU - Abdollahvand, Somayeh
AU - Paulino, Nuno
AU - Gomes, Luis
AU - Goes, Joao
N1 - Sem PDF.
This work was supported by the Portuguese Foundation for Science and
Technology (FCT/MCTES) (CTS multi-annual funding) through PEST
(PEST-OE/EEI/UI0066/2014) and DISRUPTIVE (EXCL/EEIELC/0261/2012)
and PhD Grant SFRH/BD/76626/2011.
PY - 2015/7/27
Y1 - 2015/7/27
N2 - In this paper, a new current-mode VCO-based delta-sigma modulator is presented to avoid the need to use operational-transconductance amplifiers (OTAs), which are usually the most power hungry building-blocks. The proposed hybrid structure doesn't require an explicit high-gain block in the loop filter in order to achieve high resolution with second order noise shaping. Simulation results show the proposed current-mode VCO-based ADC performance is able to achieve to SNDR/SNR of 85/85.4dB with 5MHz bandwidth with only 2dB gain in the front-end current-mode integrator. The circuit architecture uses two 4-bit pseudo-differential VCO-based quantizers, operating in parallel, and two current-steering DACs providing intrinsic dynamic element matching (DEM).
AB - In this paper, a new current-mode VCO-based delta-sigma modulator is presented to avoid the need to use operational-transconductance amplifiers (OTAs), which are usually the most power hungry building-blocks. The proposed hybrid structure doesn't require an explicit high-gain block in the loop filter in order to achieve high resolution with second order noise shaping. Simulation results show the proposed current-mode VCO-based ADC performance is able to achieve to SNDR/SNR of 85/85.4dB with 5MHz bandwidth with only 2dB gain in the front-end current-mode integrator. The circuit architecture uses two 4-bit pseudo-differential VCO-based quantizers, operating in parallel, and two current-steering DACs providing intrinsic dynamic element matching (DEM).
KW - delta-sigma analog to digital converter (ΔΣ-ADC)
KW - quantizer
KW - VCO-based
UR - http://www.scopus.com/inward/record.url?scp=84946197785&partnerID=8YFLogxK
U2 - 10.1109/ISCAS.2015.7169077
DO - 10.1109/ISCAS.2015.7169077
M3 - Conference contribution
AN - SCOPUS:84946197785
T3 - IEEE International Symposium on Circuits and Systems
SP - 2037
EP - 2040
BT - 2015 IEEE International Symposium on Circuits and Systems (ISCAS)
PB - Institute of Electrical and Electronics Engineers (IEEE)
CY - New York
T2 - IEEE International Symposium on Circuits and Systems, ISCAS 2015
Y2 - 24 May 2015 through 27 May 2015
ER -