In-memory computation system with drift compensation circuit

Abstract

A circuit includes a memory array with memory cells arranged in a matrix of rows and columns, where each row includes a word line connected to the memory cells of the row, and each column includes a bit line connected to the memory cells of the column. Computational weights for an in-memory compute operation (IMCO) are stored in the memory cells. A word line control circuit simultaneously actuates word lines in response to input signals providing coefficient data for the IMCO by applying word line signal pulses. A column processing circuit connected to the bit lines processes analog signals developed on the bit lines in response to the simultaneous actuation of the word lines to generate multiply and accumulate output signals for the IMCO. Pulse widths of the signal pulses are modulated to compensate for cell drift. The IMCO further handles positive/negative calculation for the coefficient data and computational weights.