A Complementary Recycling Operational Transconductance Amplifier with Data-Driven Enhancement of Transconductance

An improved operational transconductance amplifier (OTA) is presented in this work. The fully differential OTA adopts the current recycling technique and complementary NMOS and PMOS input branches to enhance the total transconductance. Moreover, in order to achieve higher current efficiency, a data-...

Full description

Saved in:
Bibliographic Details
Published in:Electronics (Basel) 2019-12, Vol.8 (12), p.1457
Main Authors: Li, Xiang, Hou, Bo, Ju, Chunge, Wei, Qi, Zhou, Bin, Zhang, Rong
Format: Article
Language:English
Subjects:
Amplification
Circuits
CMOS
Comparators
Current efficiency
Efficiency
Feedback loops
Metal oxide semiconductors
Operational amplifiers
Power consumption
Recycling
Slew rate
Threshold voltage
Topology
Transconductance
Transistors
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:An improved operational transconductance amplifier (OTA) is presented in this work. The fully differential OTA adopts the current recycling technique and complementary NMOS and PMOS input branches to enhance the total transconductance. Moreover, in order to achieve higher current efficiency, a data-driven biasing circuit was developed to dynamically adjust the power consumption of the amplifier. Two comparators were added to detect the voltage difference at the input nodes, and when the differential input is large enough to activate either comparator, extra biasing current is activated and poured into the amplifier to enhance its slew rate and gain-bandwidth product (GBW). The threshold voltage of the complementary recycling folded cascode (CRFC)-based comparator is configured to suppress overshoot. Complementary common-mode feedback (CMFB) topology with local CMFB structure is built to acquire high common-mode gain. The OTA was fabricated in SMIC 0.18- μ m CMOS technology. The experimental result based on a capacitive feedback loop shows that the data-driven operation improves the average slew rate of the amplifier from 10.2 V/ μ s to 55.5 V/ μ s while the power only increases by 150%. The OTA has good potential to satisfy the fast settling demands for capacitive sensing circuits.
ISSN:2079-9292
2079-9292
DOI:10.3390/electronics8121457