Daisy chain circuit for serial connection of neuron circuits

摘要

A daisy chain circuit (600) is placed in each neuron circuit of a neural network. Each daisy chain circuit is serially connected to the two adjacent neuron circuits, so that all the neuron circuits are structured as a chain. Its main role is to distinguish between the two possible states of the neuron circuit: engaged or free and moreover to identify the first free "or ready to learn" neuron circuit in the chain. This distinction is based on the respective values of the input (DCI) and output (DCO) signals of the daisy chain circuit. The ready to learn neuron circuit is the only neuron circuit of the neural network whose said input and output signals are complementary to each other. It is built around a 1-bit register (601) controlled by a store enable signal (ST) which is set active at initialization or during the learning phase when a new neuron circuit must be engaged. The input terminal of the first daisy chain circuit in the chain is connected to a first logic value, so that it is the ready to learn neuron circuit by construction after initialization. After initialization, all the registers of the chain are set to a second logic value. In the learning phase, the 1-bit register contents of the ready to learn neuron circuit is set to the said first logic value by the store enable signal, it is said "engaged". The following neuron circuit in the chain then becomes the new ready to learn neuron circuit. In addition, the daisy chain circuit is adapted to generate various control signals e.g. the control signal (RS) that allows to load the input vector components in the weight memory of only the ready to learn neuron circuit during the recognition phase. <MATH>