Method for on chip sensing of SONOS VT window in non-volatile static random access memory

摘要

A system and method for determining a SONOS VT window using a current sensing scheme is disclosed. The present invention creates a first current path and a second current path through the volatile and non-volatile sections of an nvSRAM memory cell. The erase threshold voltage of the first edge of the window is determined when current is detected in the first path. The program voltage of the second edge of the window is determined when current is detected in the second path. Accordingly, the voltage used to power a plurality of SONOS transistors may be set using the values of the first and second threshold edges to determine the VT window.