Design of Interface Circuits and Lightweight PUF for TMR Sensors

Authors:
Publisher website
Google Scholar
Abstract
The micro-magnetometers with high-resolution digital output are widely used in military and civilian fields. We proposed a novel high-precision interface circuit with optimized chopper technique and switched-capacitor modulator for tunneling magnetoresistance (TMR) sensors. This work also proposes a novel method to create lightweight physically unclonable function (PUF) by using existing TMR devices. The sigma-delta modulator converts the sensor signal into a robust digital output and maintain the signal-to-noise ratio (SNR) of the front-end circuit. We also take advantage of inherent variations of TMR sensors to generate PUF responses that are similarly unique and unclonable. The interface circuit is fabricated by 0.35μm CMOS process from Shanghai Huahong foundry. The active area of ASIC is only about 3 mm×2.7 mm. The interface circuit can achieve a SFDR of 120dB and a SNR of 98 dB at a sampling frequency of 200kHz. The TMR magnetometers were tested in an environment of three-layer magnetic shielding. Our proposed PUF is also tested in terms of uniqueness and reliability.
Funding Information
  • Natural Science Foundation of Ningbo Municipality (2021S066)
  • National Natural Science Foundation of China (62001257, 62234008)

This publication has 25 references indexed in Scilit: