Patent ID: 7274597

Claim:
A method of programming an electrically erasable programmable read-only memory cell capable of storing at least one information bit, said memory cell having a charge-trapping region, said method comprising: programming the information bit by injecting and storing electrical charge in the charge-trapping region by applying a programming signal having a fixed voltage to the memory cell during a first period of time; applying a programming signal having a constant current to the memory cell during a second period of time, said applied constant current resulting in said programming signal having a variable voltage at said memory cell; predefining a threshold value for said variable voltage; measuring said variable voltage at said memory cell during said second period of time; continuing applying said constant current programming signal to inject and store electrical charge in said charge trapping region such that said variable voltage increases; ending said injecting and storing when said variable voltage exceeds said predefined threshold value; and wherein the constant current applied during the second period of time is at a current level greater than, equal to, or smaller than, a current level reached at the end of the first period of time.