Xilinx, Inc.
Softmax circuit

Abstract:

Disclosed approaches for circuitry that implements a softmax function include difference calculation circuitry configured to calculate differences between combinations of elements, z.sub.k-z.sub.j, of a vector. First lookup circuitry is configured to lookup and output representations of exponential values, e.sup.z.sup.k.sup.-z.sup.j associated with the differences in response to input of the differences. Each adder circuit of N adder circuits sums a subset of the exponential values output from the first lookup circuitry and a value of 1. The sum output by each adder circuit denotes a denominator of a plurality of denominators of the softmax function. Second lookup circuitry is configured with quotients and looks-up and outputs quotients associated with the plurality of denominators as results of the softmax function.