Abstract
The readout of high impedance sensors and sampled voltage references [1]
requires amplifiers with both low offset and low input current. Chopper amplifiers
can achieve low offset, but the switching of their input chopper gives rise to
significant input current (40 to 110pA) [2-4]. Auto-zero (AZ) amplifiers require
less input switching, but exhibit more voltage noise. However, ping-pong
amplifiers continuously swap two auto-zeroed input stages, leading to more
switching [5,7]. In this work, an AZ stabilized topology is proposed, in which a
single amplifier is always present in the signal path. Only one input switch is
required, resulting in an input current of 0.6pA (max), a 66× improvement on the
state-of-the art [4]. Furthermore, a digitally assisted offset-reduction scheme
reduces its low-frequency (LF) noise to the theoretical √5× limit. It also achieves
a state-of-the-art maximum offset of 0.6μV.
requires amplifiers with both low offset and low input current. Chopper amplifiers
can achieve low offset, but the switching of their input chopper gives rise to
significant input current (40 to 110pA) [2-4]. Auto-zero (AZ) amplifiers require
less input switching, but exhibit more voltage noise. However, ping-pong
amplifiers continuously swap two auto-zeroed input stages, leading to more
switching [5,7]. In this work, an AZ stabilized topology is proposed, in which a
single amplifier is always present in the signal path. Only one input switch is
required, resulting in an input current of 0.6pA (max), a 66× improvement on the
state-of-the art [4]. Furthermore, a digitally assisted offset-reduction scheme
reduces its low-frequency (LF) noise to the theoretical √5× limit. It also achieves
a state-of-the-art maximum offset of 0.6μV.
| Original language | English |
|---|---|
| Title of host publication | 2018 IEEE International Solid-State Circuits Conference, ISSCC 2018 |
| Subtitle of host publication | Digest of Technical Papers |
| Publisher | IEEE |
| Pages | 50-52 |
| Number of pages | 3 |
| ISBN (Electronic) | 978-1-5090-4940-0 |
| ISBN (Print) | 978-1-5386-2227-8 |
| DOIs | |
| Publication status | Published - 2018 |
| Event | 65th IEEE International Solid-State Circuits Conference, ISSCC 2018 - San Francisco, United States Duration: 11 Feb 2018 → 15 Feb 2018 |
Publication series
| Name | Digest of Technical Papers |
|---|---|
| Volume | 61 |
| ISSN (Print) | 0193-6530 |
Conference
| Conference | 65th IEEE International Solid-State Circuits Conference, ISSCC 2018 |
|---|---|
| Country/Territory | United States |
| City | San Francisco |
| Period | 11/02/18 → 15/02/18 |
Bibliographical note
Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-careOtherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.