The outcomes of a research within HERMES project by our consortium partner Aarhus University - Dept. of Engineering – were presented at 2021 IEEE Custom Integrated Circuits Conference (CICC) - Amplifier Techniques session.
On Monday, 26 April 2021 the Engineering team coordinated by PI prof Farshad Moradi, and represented by Hai Au Huynh, presented "Input Impedance Multi-Channel Neural Recording Amplifier with 0.77 µVrms Input-Referred Noise for Deep Brain Implants" a paper by Hai Au Huynh, Milad Zamani, Margherita Ronchini, Homan Farkhani, Farshad Moradi
AU provides expertise in microelectronics and integrated circuits (IC) design and implementation. Their paper presents a 4-channel analog front-end comprising of the input buffers, capacitive coupled chopper-stabilized amplifier, and programmable gain amplifier.
The input buffer ensures an ultra-high input impedance of 53GΩ@DC to tolerate high electrode-tissue impedance mismatch. The output impedance of the buffers is optimized to reduce the effect of multi-channel on CMRR. The amplifier consumes 4.3μW/ch while operating with low input-referred noise at 0.77μVrms and 1.75μVrms over 2Hz-200Hz and 200Hz-2.4kHz, respectively.
The IEEE Custom Integrated Circuits Conference is a premier conference devoted to IC development. The conference sessions present original first published technical work and innovative circuit techniques that tackle practical problems. CICC is the conference to find out how to solve design problems, improve circuit design techniques, get exposure to new technology areas, and network with peers, authors and industry experts.
In particular, the Amplifier Techniques session showcased recent advances in amplifier techniques for biopotential sensing, covering many aspects such as electrode offset cancellation, area efficiency and ultra-high input impedance.