3d nor flash based in-memory computing

Abstract

Compute-in-memory CIM operations using signed bits produce signed outputs. A circuit for CIM operations comprises an array of memory cells arranged in columns and rows, memory cells in columns connected to corresponding bit lines, and memory cells in rows connected to corresponding word lines. The array is programmable to store signed weights in sets of memory cells, the sets being operatively coupled with a corresponding pair of bit lines and a corresponding pair of word lines. Word line drivers are configured to drive true and complement voltages representing signed inputs on respective word lines in selected pairs of word lines. Sensing circuits are configured to sense differences between first and second currents on respective bit lines in selected pairs of bit lines and to produce signed outputs for the selected pairs of bit lines as a function of the difference.