Analog Implementation of the Softmax Function

TL;DR

This paper introduces an analog circuit design for the Softmax function, demonstrating modular scalability and high accuracy through experimental and simulation results with BJT and NMOS technologies.

Contribution

It presents a novel modular analog implementation of Softmax that scales linearly and achieves high computational accuracy in both experimental and simulation settings.

Findings

Accuracy within 4.2% in prototype

Simulation accuracy within 1.3% (BJT)

Simulation accuracy within 0.9% (NMOS)

Abstract

An analog implementation of the Softmax activation function is presented. A modular design is proposed, scaling linearly with the number of inputs and outputs. The circuit behaves similarly using both a BJT and NMOS design scheme. Experimental results extracted from a BJT breadboard prototype presents computational accuracy within 4.2% margin of error. Simulation data presents accuracy within 1.3% margin of error for BJT and 0.9% margin of error for NMOS design schemes.