Organic Log‐Domain Integrator Synapse

Abstract

Synapses play a critical role in memory, learning, and cognition. Their main functions include converting presynaptic voltage spikes to postsynaptic currents, as well as scaling the input signal. Several brain‐inspired architectures have been proposed to emulate the behavior of biological synapses. While these are useful to explore the properties of nervous systems, the challenge of making biocompatible and flexible circuits with biologically plausible time constants and tunable gain remains. Here, a physically flexible organic log‐domain integrator synaptic circuit is shown to address this challenge. In particular, the circuit is fabricated using organic‐based materials that are electrically active, offer flexibility and biocompatibility, as well as time constants (critical in learning neural codes and encoding spatiotemporal patterns) that are biologically plausible. Using a 10 nF synaptic capacitor, the time constant reached 126 and 221 ms before and during bending, respectively. The flexible synaptic circuit is characterized before and during bending, followed with studies on the effects of weighting voltage, synaptic capacitance, and disparity in presynaptic signals on the time constant.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 31, 2021
Source ID
10.1002/aelm.202100724

Entities

People

  • Elisa Donati
  • Giacomo Indiveri
  • Mohammad Javad Hosseini
  • Robert A Nawrocki

Organizations

  • Purdue University
  • United States Naval Research Laboratory
  • University of Zurich

Tags

Readers

  • Distributed Systems and Data Platform Development
  • Integrated Circuit Design and Technology.
  • Neuroscience