TY - GEN
T1 - A continuous-time ΣΔ modulator with a Gm-C input stage, 120-dB CMRR and -87 dB THD
AU - Sarhangnejad, Navid
AU - Wu, Rong
AU - Chae, Youngcheol
AU - Makinwa, Kofi A.A.
PY - 2011
Y1 - 2011
N2 - This paper describes a precision continuous-time ΣΔ modulator for sensor applications. To achieve high input impedance, it uses a G m-C integrator as its input stage. The non-linearity of this stage is cancelled by a replica transconductor in the modulator's feedback path, which is driven by a low-pass filtered version of the modulator's single-bit output. Since the filter adds extra delay, this path is bypassed at high frequencies to preserve modulator stability. The modulator was implemented in a 0.7-μm CMOS process and achieves 79-dB SNR/SNDR and 82-dB DR over a 100-Hz signal bandwidth. It also achieves 32-μV offset, 120-dB CMRR, 120-dB PSRR, and -87 dB THD.
AB - This paper describes a precision continuous-time ΣΔ modulator for sensor applications. To achieve high input impedance, it uses a G m-C integrator as its input stage. The non-linearity of this stage is cancelled by a replica transconductor in the modulator's feedback path, which is driven by a low-pass filtered version of the modulator's single-bit output. Since the filter adds extra delay, this path is bypassed at high frequencies to preserve modulator stability. The modulator was implemented in a 0.7-μm CMOS process and achieves 79-dB SNR/SNDR and 82-dB DR over a 100-Hz signal bandwidth. It also achieves 32-μV offset, 120-dB CMRR, 120-dB PSRR, and -87 dB THD.
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U2 - 10.1109/ASSCC.2011.6123556
DO - 10.1109/ASSCC.2011.6123556
M3 - Conference contribution
AN - SCOPUS:84856364618
SN - 9781467303989
T3 - 2011 Proceedings of Technical Papers: IEEE Asian Solid-State Circuits Conference 2011, A-SSCC 2011
SP - 245
EP - 248
BT - 2011 Proceedings of Technical Papers
T2 - 7th IEEE Asian Solid-State Circuits Conference, A-SSCC 2011
Y2 - 14 November 2011 through 16 November 2011
ER -