Open AccessPVT compensated inverter‐based OTA for low‐voltage CT sigma‐delta modulators
Author(s) -
Aguirre P.C.C.,
Susin A.A.
Publication year - 2018
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2018.6327
Subject(s) - transconductance , delta sigma modulation , robustness (evolution) , inverter , voltage , transistor , electronic engineering , cmos , operational transconductance amplifier , bandwidth (computing) , amplifier , electrical engineering , materials science , operational amplifier , engineering , telecommunications , biochemistry , chemistry , gene
An inverter‐based operational transconductance amplifier (OTA) robust to process, voltage and temperature (PVT) variations is proposed in this Letter to enable the design of low‐voltage power‐efficient continuous‐time sigma‐delta modulators (CT‐SDMs). The proposed OTA significantly reduces the unity gain‐bandwidth variation across PVT corners while presenting a DC gain of 41.9 dB at nominal conditions when operated at 0.6 V. The effectiveness of the proposed circuit was verified in a 180 nm CMOS process by transistor‐level simulations including PVT variations and mismatch. Also, a 0.6 V third‐order CT‐SDM is designed to verify the robustness against voltage and temperature variations.