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16:38
Bridging the Bio-Electronic Interface with Biofabrication
Published on: June 6, 2012
A bionics chemical synapse.
Surachoke Thanapitak1, Christofer Toumazou
1Division of Electrical and Electronic Engineering, Imperial College London, London SW7 2AZ, UK. st706@ic.ac.uk
IEEE Transactions on Biomedical Circuits and Systems
|July 16, 2013
Summary
This study presents CMOS circuits mimicking brain chemical synapses, including AMPA, NMDA, and GABA receptors. These biomimetic circuits demonstrate efficient, low-power operation for neurotransmitter sensing and signal processing.
Area of Science:
- Neuroscience
- Electrical Engineering
- Biomedical Engineering
Background:
- Chemical synapses are crucial for neural information processing.
- Existing electronic models often lack biological realism or efficiency.
- Mimicking synaptic function in silicon is key for advanced neuromorphic systems.
Purpose of the Study:
- To design and implement CMOS circuits for key excitatory (AMPA, NMDA) and inhibitory (GABA) chemical synapses.
- To develop a glutamate sensor using a modified ISFET.
- To validate circuit performance against mathematical models and assess power efficiency.
Main Methods:
- Current-mode CMOS circuit design for AMPA, NMDA, and GABA receptors.
- Utilizing a modified Ion-Sensitive Field-Effect Transistor (ISFET) with immobilized glutamate oxidase for glutamate detection.
- Electrical signal representation for GABAergic neurotransmission.
- Mathematical modeling and circuit simulations.
- Chip fabrication in 0.35-μm AMS CMOS technology.
Main Results:
- Successful implementation of biomimetic chemical synapse circuits for glutamate and GABA.
- Measured results from the fabricated circuits closely matched simulation predictions.
- Achieved a total power consumption of 168.3 μW for the chip.
- The chip occupied a total area of 3 mm².
Conclusions:
- The developed CMOS circuits effectively emulate the function of biological chemical synapses.
- The integrated glutamate sensor demonstrates reliable sensing capabilities.
- The low power consumption and compact area make these circuits suitable for neuromorphic applications.
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