Publications by Alexandre Schmid

A Sequential High-Frequency Switched-Capacitor Neuro-Stimulation Technique with 77% Power Efficiency

This paper proposes a new energy-efficient technique for high-frequency switched-capacitor stimulation systems. The proposed sequential high-frequency switched-capacitor (S-HFSC) structure employs a two-step charge transfer technique to reduce the voltage ...

SPRINGER BIRKHAUSER2025

Analysis of Power Consumption and Propagation Delay in Voltage Level Shifters

Alexandre Schmid, Mehdi Saberi

The analysis of the operation of non-linear circuits such as voltage level shifters and latched comparators and therefore prediction of their propagation delay and power consumption are challenging. This is because the operating points of the employed non- ...

Institute of Electrical and Electronics Engineers (IEEE)2025

Split weight distribution learning for binary neural networks exploiting nano-memristive graphene/sumanene/graphene devices

Alexandre Schmid

Research in artificial intelligence (AI) and neural network (NN) technologies has been boosted by recent hardware advances, while the emergence of self-synthesized materials such as nanocarbons has attracted much attention to overcome the limitations of Si ...

IOP Publishing Ltd2025

Analysis of Integrator-Differentiator Transimpedance Amplifiers: Speed and Gain Tradeoff Introduced by Parasitic Capacitances

Alexandre Schmid, Matteo Dal Peraro, Mehdi Saberi

In this paper, the frequency behavior and stability of current recording systems employing continuous-time integrator-differentiator transimpedance amplifiers (TIAs) are analyzed. The proposed comprehensive analysis provides designers helpful design rules ...

Institute of Electrical and Electronics Engineers (IEEE)2025

A Two-Wired High Input Impedance and High CMRR Active Electrode Insensitive to Component Mismatch

Alexandre Schmid, Mehdi Saberi

This article proposes a new two-wired amplifying active electrode (AE), presenting a high input impedance and a high common-mode rejection ratio (CMRR). In the proposed structure, the input impedance and the CMRR of the system are considerably increased by ...

Ieee-Inst Electrical Electronics Engineers Inc2024

An Analysis of an ASK Demodulator With Dual Self-Biased Separated Voltages for Implantable Applications

Catherine Dehollain, Alexandre Schmid

A new structure of low-power demodulator named 'separated-Vb' amplitude shift keying (ASK) demodulator is proposed. The circuit is based on the switching behavior of the core digital shaper with different bias voltages, which improves its operation at low ...

2024

A Wireless Power Conversion Chain With Fully On-Chip Automatic Resonance Tuning System for Biomedical Implants

Catherine Dehollain, Alexandre Schmid

This paper presents a wireless power conversion system designed for biomedical implants, with integrated automatic resonance tuning. The automatic tuning mechanism improves power transfer efficiency (PTE) by finely tuning the resonant frequency of the powe ...

Ieee-Inst Electrical Electronics Engineers Inc2024

A High-Gain Transimpedance Amplifier Using Highly-Linear and Symmetric Multi-Stage Pseudo-Resistors

Alexandre Schmid, Mehdi Saberi

© 2024 IEEE.This paper presents a high gain, low power, and highly linear structure for integrator-differentiator transimpedance amplifiers (TIAs) employed in biological recording systems. In order to improve the linearity of the structure, a symmetric and ...

Institute of Electrical and Electronics Engineers Inc.2024

An offset-enhanced active rectifier with delay compensated active diodes for wirelessly powered biomedical implants

Catherine Dehollain, Alexandre Schmid

This letter presents the design of a 13.56 MHz offset-enhanced full-wave active rectifier, tailored for wirelessly powered biomedical implants. The design incorporates digitally assisted, delay-compensated active diodes and symmetrical bulk biasing in the ...

2024

Wireless Power and Data Transceiver in A Central Implanted Unit for Biomedical Applications

Catherine Dehollain, Alexandre Schmid

This paper presents a wireless power and data transmitter designed for central implanted units (CIUs) in the context of biomedical applications. This CIU is positioned within the human body or brain to supply power from stored battery energy to specific im ...

Institute of Electrical and Electronics Engineers Inc.2024

A Low-Power and High-Precision Time- Domain Winner-Take-All Circuit Based on the Group Search Algorithm

Alexandre Schmid

In this paper, a low-power and high-precision time-domain winner-take-all (WTA) circuit is proposed which is based on a novel group search algorithm. The proposed method, which determines the winner input within a single clock cycle, not only demands no mu ...

Institute of Electrical and Electronics Engineers Inc.2024

Wirelessly Powered and Bi-Directional Data Communication System With Adaptive Conversion Chain for Multisite Biomedical Implants Over Single Inductive Link

Catherine Dehollain, Alexandre Schmid

A wirelessly powered and data communication system is presented which is implemented as a full system, designed for multisite implanted biomedical applications. The system is capable of receiving wireless power and data communication for each implant separ ...

2024

A High-Precision and High-Dynamic-Range Current-Mode WTA Circuit for Low-Supply-Voltage Applications

Alexandre Schmid, Mehdi Saberi

This brief proposes a low-voltage, high-precision, and high-dynamic-range current-mode analog winner-take-all (WTA) circuit. The proposed structure employs a new high-gain stage as a feedback network between the input node of each cell and the common node ...

2024

Programmable Seizure Detector Using a 32-bit RISC Processor for Implantable Medical Devices

Alexandre Schmid, Keyvan Farhang Razi

A programmable patient-customized epileptic seizure detector is proposed in this paper to enable neurologists and patients to have constructive interactions with the implantable medical device. The programmability feature is enabled by designing a low-powe ...

IEEE2023

High Input Impedance Front-End Amplifier for Noncontact Bio-Potential Recording

Alexandre Schmid

In this paper, a high input impedance front-end amplifier is proposed for non-contact bio-potential recording systems. The proposed structure uses a positive feedback network to deliver a neutralization current back to the input node of the circuit to neut ...

Institute of Electrical and Electronics Engineers Inc.2023

Power Feedback Control Unit for Closed-Loop Wirelessly Powered Biomedical Implants

Catherine Dehollain, Alexandre Schmid

Effective power management is crucial in designing wirelessly powered implants that have a long operational lifetime. It ensures that the received power is optimized for efficient operation and prevents damage caused by excessive or insufficient powering. ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Digital One-Shot Charge-balancing Method for Implantable Current-Mode Electrical Stimulation

Alexandre Schmid, Keyvan Farhang Razi

A low-power digital charge balancing system, which ensures the safe operation of constant-current biphasic stimulation is presented. The concept of the proposed charge-balancing technique is to utilize a hybrid method consisting of anodic pulse modulation ...

IEEE2023

A 13.56MHz Active Rectifier with Digitally-Assisted and Delay Compensated Comparators for Biomedical Implantable Devices

Catherine Dehollain, Alexandre Schmid

This paper presents the design of a 13.56 MHz full-wave active rectifier that utilizes digitally-assisted and delay compensated comparators for wirelessly powered biomedical implants. The proposed design employs delay compensation and digital assistance te ...

New York2023

Design of a Dual-Band Wireless Power and Data Transfer Coil for Multisite Biomedical Implants

Catherine Dehollain, Alexandre Schmid

This paper introduces a dual-band inductive link designed to operate at both 6.78 and 13.56 MHz in the industrial, scientific, and medical (ISM) bands. The primary aim is to facilitate wireless power and data transmission in multisite biomedical implants. ...

New York2023

A Delay and Power Efficient Voltage Level Shifter with Low Leakage Power

Alexandre Schmid, Mehdi Saberi

This paper presents a new power-efficient and high-speed voltage level shifter. In the proposed structure, the existing contentions at the internal nodes are reduced using auxiliary transistors and feedback networks, leading to a significant reduction in t ...

IEEE2023