US Patent 7512507 Die based trimming

Methods and structures are described to provide trims for die on a wafer. The trims are set on a die-by-die basis instead of a wafer basis. Accordingly, the individual die are more finely tuned and more die operate at the target specifications so that yield is increased. In an embodiment, the odd and even blocks of each non volatile memory die are erased and then programmed to test the program time. Statistical analysis of the tested program times is performed. Based on this analysis the trim values are determined and programmed into the die. Accordingly, each die on a wafer has its individual trim settings.