Neural network integrated circuit with fewer pins

A method for searching and sorting which neuron circuit in a network of such circuits has a closest distance between an internal training vector and a test vector, the method comprising the steps of:

• interconnecting a plurality of neuron circuits with a single-wire wire-logic bus;
• computing a distance measure in each of said plurality of neuron circuits derived from a privately stored internal training vector and a publicly broadcast test vector;
• comparing respective said distance measures for all said plurality of neuron circuits in bit parallel fashion;
• eliminating each one of said plurality of neuron circuits that does not have a closest distance between an internal training vector and a test vector bit-by-bit in successive cycles until all bit positions of said distance measures are checked;
• and
• announcing a closest-distance one of said plurality of neuron circuits with a unique identification code.

A neural network integrated circuit (IC), comprising:

• a neuron circuit that compares test vectors with learned vectors and that fires when any test vector comes within a predetermined distance of a learned vector;
• a distance register connected to the neuron circuit and that provides for a distance measure to be stored;
• a wire-logic one-wire bus that interconnects the neuron circuit with similar neuron circuits in a larger neural network system;
• a data-selector that communicates each bit position of the distance register out on to said wire-logic one-wire bus in successive bit-comparison cycles;
• a snoop circuit for sensing a logic-state on said wire-logic one-wire bus during each said successive bit-comparison cycles;
• and
• a closest-hit calculator connected to both the data-selector and the snoop circuit, and for providing a bit-for-bit test of the logic states successively communicated on the wire-logic one-wire bus that determine if the distance register is storing a distance measure that is a least-of-all distance measures stored in any distance registers of any of said similar neuron circuits in said larger neural network system.