Patent ID: 7038928

Claim:
A method of determining an optimal reading voltage for reading a two-sided non-volatile memory programmed with a threshold voltage Vt, comprising: programming a first side of a memory cell to Vt; measuring an I 1 -Vg curve of the first side and an I 2 -Vg curve of a second side of the memory cell, wherein Vg is a voltage applied to a gate of the memory cell; plotting a Gm 1 -Vg curve and a Gm 2 -Vg curve from the I 1 -Vg curve and the I 2 -Vg curve, wherein Gm 1 =dI 1 /dVg and Gm 2 =dI 2 /dVg; and determining the optimal reading voltage Vg O as the voltage at an intersection of the Gm 1 -Vg curve and the Gm 2 -Vg curve.