E6.1 - Hierarchical Digital Offset Voltage Trimming of Fully-Differential Amplifiers in Self-X Sensor Electronics
- Event
- SMSI 2023
2023-05-08 - 2023-05-11
Nürnberg - Band
- Lectures
- Chapter
- E6 - Sensor Interface Electronics
- Author(s)
- S. Alraho, A. König, Q. Zaman - Technical University of Kaiserslautern, Kaiserslautern (Germany)
- Pages
- 264 - 265
- DOI
- 10.5162/SMSI2023/E6.1
- ISBN
- 978-3-9819376-8-8
- Price
- free
Abstract
This paper presents an improved approach to the digital offset voltage calibration scheme of fully differential amplifiers by splitting the adaptation process into two levels using separated coarse and fine digital-to-analog (DAC) current steering converters. The key feature is to avoid the matching complexity of using a single high-resolution DAC. Furthermore, the dynamic offset trimming process can be repeated based on the second DAC only, leading to a reduction in the calibration time. The achieved results based on Monte Carlo simulation show the ability to calibrate the offset voltage of the fullydifferential instrumentation amplifier (In-Amp) below 100 μV for tackling offset voltage around ± 9 mV. The circuit is designed using XFAB 0.35 μm technology and verified with Cadence Virtuoso tools.