Defect mitigation in a crossbar-based computing environment

An apparatus comprising:

• a crossbar array configured to receive an input signal and produce a raw output signal, a row wire within the crossbar array, wherein the row wire includes a defective device having a defect pattern, wherein the defect pattern includes an un-tunable conductance of the defective device, wherein the raw output signal is produced by passing the input signal through the defective device;
• a compensation module configured to:
• determine an error signal resulted from passing the input signal through the defective device;
• and
• produce a compensated output signal configured to be outputted from the crossbar array in place of the raw output signal in accordance with the error signal.

A method comprising:

• identifying a defect pattern of an apparatus, wherein the apparatus includes:
• a first row wire;
• a second row wire;
• a first crossbar array receiving an input signal, wherein the first row wire and the second row wire are in the first crossbar array;
• a plurality of first devices on the first row wire;
• and
• a plurality of second devices on the second row wire, wherein the plurality of first
• devices and the plurality of second devices include a defective device;
• detecting one or more rows, each of which has at least one defect;
• comparing the one or more rows to a set of rows in a target conductance matrix;
• identifying a best-fitting row in the target conductance matrix with the target conductance that is within a user-defined approximation to conductance of a defect;
• programming the best-fitting row;
• and shuffling the input signal to the best-fitting row;
• and
• in accordance with a first determination that all defective rows have been examined:
• programming remaining rows that are without defect;
• determining an error current with the target conductance;
• and
• deducting a contribution of the error current from the raw output signal to produce a compensated output signal, in accordance with a second determination that all defective rows have not been examined repeating step of the comparing, the identifying, the programming and the shuffling.