An analogue VLSI implementation of an integrate-and-fire neural network for real-time auditory data processing
Mark Glover · ERA · 1999
Neuromorphic engineering is the modelling of neurobiological systems -in silicon and I or through computer simulation.It draws inspiration from neurobiology in an attempt to gain insight into biological processes, or to develop novel circuits and solutions to real engineering problems.This thesis describes the development of a hardware implementation of the integrate-andfire neural network stage of the sound segmentation algorithm.It discusses issues involved in the development of novel aVLSI techniques capable of modelling biologically realistic processes.Comparisons are made between hardware and software implementations of the integrate-and-fire neural networks for real time data.Various approaches have been investigated.These include: fixed / variable interconnect, fixed I variable weight strengths, programmable biologically realistic time constants.Cas- cading techniques have been used to investigate the feasibility of inter-chip communication.Arguments are proposed for design modifications.Results show that aVLSI circuits can be produced which will realistically model biological processes and that there is a high degree of similarity between hardware and software implentation of the integrate-and-fire neural network.Suggestions are made for further investigation and work which include circuit modifications to increase flexibility and performance.. ToAlister Hamilton I Leslie Smith for their help, advice, support and generally good humour.• Over the 3 years of my studentship I have seen my people come and go from A2:3, these people deserve special mention:-Andy Connelly (3 years) -a man who took giving group talks to a new highs and like me has a warped sense of humour.-Marcus Alphey (2 years) -a man who could answer any program question I ever put to him, bar the one which will haunt him till the end of his days.-Cati Breslin a.k.aCollins (2 years) -whose knowledge of the brain was truly scary.-Mark Harding (1 year) -web programmer and general KDT support manager supreme.-Morgan Tamplin (1 year and moving out) -was it something we said.• To those gallant souls and maintainers of ISG harmony Emma Braithwaite, Peter Edwards, Robin Woodburn.Who endured the dubious pleasure of proof reading my thesis over and over and over again.Their agony is now over.• I must thank those gentleman and scholars who like me suffered the torment and pain of CAD chip design Bill Buchan, John Breslin, David Mayes, Konstandinos Papathanasiou, Torsten Lehmann for their input and support through it all.• Thanks to Andy Myles and Neil Marston for maintaining the groups level of realism,