Abstract
This paper presents a programmable analog synapse for use in both feedforward and feedback neural networks. The synapse consists of two complementary floating-gate MOSFETs which are programmable in both directions by Fowler-Nordheim tunneling. The P-transistor and the N-transistor are programmable independently with pulses of different amplitude and duration, and hence finer weight adjustment is made possible. An experimental 4x4 synapse array has been designed, which in addition has 32 analog CMOS switches and x-y decoders to select a synapse cell for programming. It has been fabricated using a standard 2-µm, double-polysilicon CMOS technology. Simulation results confirm that output current of synapse is proportional to the product of the input voltage and weight and also shows both inhibitory and excitatory current. Current summing effect has been observed at the input of a neuron. This array is designed using modular and regular structured elements, and hence is easily expandable to larger networks.
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© 1992 Springer Science+Business Media Dordrecht
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Kim, S., Shin, YC., Bogineni, N.C.R., Sridhar, R. (1992). A Programmable Analog CMOS Synapse for Neural Networks. In: Takefuji, Y. (eds) Analog VLSI Neural Networks. The Springer International Series in Engineering and Computer Science, vol 191. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-3582-9_8
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DOI: https://doi.org/10.1007/978-1-4615-3582-9_8
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