Method for programming a reference cell
First Claim
1. In an integrated circuit memory on a die having an array of memory cells each exhibiting a native threshold voltage value, a method for programming a reference cell comprising the steps of:
- a) driving a golden cell on the die with a predetermined external gate voltage value;
b) programming the reference cell a predetermined amount, the reference cell being driven by a standard gate voltage value which is greater than the predetermined external gate voltage value;
c) sensing the program state of the reference cell relative to the golden cell while the golden cell is driven with the predetermined external gate voltage value; and
d) repeating steps b) and c) until the sensing step indicates that the reference cell has been programmed an amount sufficient to pass a first preselected read operation (V_GB).
7 Assignments
0 Petitions
Accused Products
Abstract
A method for programming one or more reference cells is described. The reference cell is programmed a predetermined amount, its program state is sensed relative to a prescribed cell on the same die (e.g., a memory cell or a golden bit cell), and the programming process continues until the reference cell fails a preselected read operation. In one preferred embodiment, the memory cell used during the reference cell programming process is the cell in the memory array having the highest native threshold value. In another preferred embodiment, the memory cell used during the reference cell programming process is a native cell that is on-board the die containing the memory array, but not a cell within the memory array.
-
Citations
17 Claims
-
1. In an integrated circuit memory on a die having an array of memory cells each exhibiting a native threshold voltage value, a method for programming a reference cell comprising the steps of:
-
a) driving a golden cell on the die with a predetermined external gate voltage value; b) programming the reference cell a predetermined amount, the reference cell being driven by a standard gate voltage value which is greater than the predetermined external gate voltage value; c) sensing the program state of the reference cell relative to the golden cell while the golden cell is driven with the predetermined external gate voltage value; and d) repeating steps b) and c) until the sensing step indicates that the reference cell has been programmed an amount sufficient to pass a first preselected read operation (V_GB). - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
Specification