Gian Luca Barbruni | EPFL Graph Search

Gian Luca Barbruni achieved his BSc and his MSc in Biomedical Engineering with specialisation in Biomedical Instrumentation at the Politecnico di Torino in 2017 and 2019, respectively.During his master thesis, supervised by Prof. Danilo Demarchi from Politecnico di Torino and titled “Body Dust: Feasibility study on signal transmission for sub-100μm-size active wireless biosensors”, he spent a semester of research at Integrated Circuit Laboratory (ICLAB) of Neuchâtel under the supervision of Prof. Sandro Carrara from École Polytechnique Fédérale de Lausanne (EPFL), Switzerland. He discusses about the feasibility on creating an UltraSound (US) communication circuit to wirelessly transmit outside the body diagnostic information from multiplexed biosensors chip built on the top layer of a drinkable CMOS “Body Dust” cube. The results of the feasibility study have been published showing promising results with sub-10 µW of power consumption and a total chip area of 43 x 44 µm2.He was a Research Assistant at the Department of Electronic Engineering (DET) of Politecnico di Torino.Actually he is conducting his PhD focusing on design and fabrication of analog and digital circuits for ultra-miniaturized CMOS for vision prosthesis, directed by Prof. Diego Ghezzi at Medtronic Chair in Neuroengineering in Geneva and co-directed by Prof. Sandro Carrara at ICLAB in Neuchâtel.

A Front-End CMOS Interface Circuit With High Voltage Charge Pump and Oscillator for Capacitive Micromachined Ultrasonic Transducers

Gian Luca Barbruni, Sandro Carrara, Zhengwen Jiang, Yihe Zhao

Label-free biosensors, combined with miniaturized micro-electromechanical sensory platforms, offer an attractive solution for real-time and facile monitoring of biomolecules due to their high sensitivity and selectivity without the need for specifically labeling. Resonators have been acknowledged as an efficient technology for measuring biomolecular binding events including those involving nucleic acid and antibody. Among these, capacitive micromachined ultrasonic transducers (CMUTs) have emerged as a promising candidate for biosensing. However, their usage is often limited by the requirement for high voltage supply and continuous frequency tracking, which can result in significant parasitic effects and measurement errors. In this brief, we present a novel front-end interface circuit for a CMUTs-based biosensor. The circuit, fabricated using TSMC 0.18-mu m BipolarCMOS-DMOS (BCD) technology, incorporates an on-chip high voltage charge pump and feedback frequency monitoring. The CMUTs array features 20 x 20 circular cells, fabricated using a low-temperature direct bonding technology, with an experimental parallel-resonant frequency of 1.724 MHz and a high quality factor of up to 40.9. To fit the measured electrical characteristics, a five-element equivalent lumped element model is proposed. The high voltage charge pump provides an output voltage of similar to 20 V, while the feedback oscillator has a ms-level start-up time and a total power dissipation of 3.8 mW. The proposed frontend interface is designed to function as a stand-alone chip for CMUTs-based resonant biodetection.

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Miniaturised Wireless Power Transfer Systems for Neurostimulation: A Review

Gian Luca Barbruni, Sandro Carrara, Danilo Demarchi, Diego Ghezzi

In neurostimulation, wireless power transfer is an efficient technology to overcome several limitations affecting medical devices currently used in clinical practice. Several methods were developed over the years for wireless power transfer. In this review article, we report and discuss the three most relevant methodologies for extremely miniaturised implantable neurostimulator: ultrasound coupling, inductive coupling and capacitive coupling. For each powering method, the discussion starts describing the physical working principle. In particular, we focus on the challenges given by the miniaturisation of the implanted integrated circuits and the related ad-hoc solutions for wireless power transfer. Then, we present recent developments and progresses in wireless power transfer for biomedical applications. Last, we compare each technique based on key performance indicators to highlight the most relevant and innovative solutions suitable for neurostimulation, with the gaze turned towards miniaturisation.

2020