Granted Patent B2

US 8,971,126 · App. 14/290,315 · Granted Mar 3, 2015

Inventors: Violante Moschiano (Bacoli, IT); Daniel Elmhurst (Folsom, CA); Paul Ruby (Folsom, CA)

Assignee: Micron Technology, Inc.

G11C16/34G11C16/349G11C16/10

Abstract

Claims (63)

1. An apparatus, comprising:

an off-chip controller;

wherein the off-chip controller is configured to cause a quick charge loss compensation to be determined for at least one block of a memory; and

wherein the off-chip controller is configured to cause a wordline voltage of the memory to be adjusted according to the quick charge loss compensation, wherein the quick charge loss compensation is determined using mean threshold voltages of a tracking block at different times.

2. The apparatus of claim 1 , wherein the off-chip controller being configured to cause the quick charge loss compensation to be determined further comprises:

the off-chip controller being configured to cause program blocks in the memory to be wear leveled;

the off-chip controller being configured to cause the tracking block in the memory to be programmed with the at least one block of a memory in accordance with a specific pattern;

the off-chip controller being configured to cause a mean threshold voltage for the tracking block to be determined;

the off-chip controller being configured to cause the tracking block to be erased when a corresponding block of the memory is erased; and

the off-chip controller being configured to cause the tracking block to be re-programmed in accordance with the specific pattern when the corresponding block of the memory is programmed.

3. The apparatus of claim 2 , wherein the off-chip controller being configured to cause the wordline voltage of the memory to be adjusted comprises the off-chip controller being configured to cause a voltage level of the wordline to be adjusted equal to a difference between the mean threshold voltage and a mean threshold voltage for the tracking block after the re-programming.

4. The apparatus of claim 2 , wherein off-chip controller is configured to cause the tracking block to be programmed as a single redundant memory block for one block of the memory.

5. The apparatus of claim 2 , wherein the tracking block is a plurality of mini-arrays, each block of the memory having a separate mini-array or a portion thereof associated therewith.

6. The apparatus of claim 1 , wherein the off-chip controller being configured to cause the quick charge loss compensation to be determined comprises:

the off-chip controller being configured to cause at least a portion of a mini-array in the memory to be programmed in accordance with a specific pattern;

the off-chip controller being configured to cause a first mean threshold voltage to be determined for the at least a portion of a mini-array;

the off-chip controller being configured to cause a mini-array margin search on the at least a portion of the mini-array to be completed when a main array block associated with the mini-array is read;

the off-chip controller being configured to cause a difference to be determined between the first mean threshold voltage and a second mean threshold voltage of the at least a portion of a mini-array upon reading the main array block associated with the mini-array; and

the off-chip controller being configured to cause the at least a portion of a mini-array to be re-programmed in accordance with the specific pattern when the main array block associated with the mini-array is programmed; and

the off-chip controller being configured to cause a wordline voltage level to be adjusted by the difference between the first mean threshold voltage and second mean threshold voltage.

7. The apparatus of claim 6 , wherein the off-chip controller being configured to cause at least a portion of a mini-array to be programmed comprises the off-chip controller being configured to cause the at least a portion of a mini-array to be programmed contemporaneous to programming of the main array block associated with the mini-array.

8. An apparatus, comprising:

an off-chip controller;

wherein the off-chip controller is configured to cause program blocks in a memory to be wear leveled;

wherein the off-chip controller is configured to cause a program block of the memory and a redundant block of the memory to be programmed in accordance with a specific pattern, the program block caused to be programmed associated with the redundant block;

wherein the off-chip controller is configured to cause a mean uncycled threshold voltage to be determined for the redundant block;

wherein the off-chip controller is configured to cause the redundant block to be erased when the associated program block is erased;

wherein the off-chip controller is configured to cause the redundant block to be re-programmed in accordance with the specific pattern when the associated program block is programmed;

wherein the off-chip controller is configured to cause a current post-cycled mean threshold voltage to be determined for the redundant block; and

wherein the off-chip controller is configured to cause a wordline voltage level to be adjusted.

9. The apparatus of claim 8 , wherein the off-chip controller being configured to cause the wordline voltage level to be adjusted further comprises the off-chip controller being configured to cause the wordline voltage level to be raised by an amount equal to a difference between the uncycled mean threshold voltage and the current post-cycled mean threshold voltage for the redundant block.

10. The apparatus of claim 8 , wherein the off-chip controller being configured to cause the wordline voltage level to be adjusted further comprises the off-chip controller being configured to cause the wordline voltage level to be adjusted based on the mean uncycled threshold voltage and the current post-cycled mean threshold voltage.

11. An apparatus, comprising:

an off-chip controller;

wherein the off-chip controller is configured, for each program block in the memory, to cause the program block and at least a portion of a mini-array to be programmed in accordance with a specific pattern;

wherein the off-chip controller is configured to cause a mean uncycled threshold voltage to be determined for each at least a portion of a mini-array;

wherein the off-chip controller is configured to cause a mini-array margin search on the at least a portion of a mini-array block to be completed, when an associated program block is read, to determine a difference between a current post-cycled threshold voltage mean for the at least a portion of a mini-array and the mean uncycled threshold voltage for the at least a portion of a mini-array;

wherein the off-chip controller is configured to cause the at least a portion of a mini-array to be re-programmed in accordance with the specific pattern when the associated block is programmed; and

wherein the off-chip controller is configured to cause a wordline voltage level to be adjusted by an amount equal to the difference between the current post-cycled threshold voltage mean for the at least a portion of a mini-array and the mean uncycled threshold voltage for the at least a portion of a mini-array.

12. The apparatus of claim 11 , wherein the off-chip controller being configured, for each program block in the memory, to cause the program block and at least a portion of a mini-array to be programmed comprises the off-chip controller being configured to cause a page or a portion of a page of a mini-array to be allocated to each program block.

13. An apparatus, comprising:

an off-chip controller;

wherein the off-chip controller is configured to cause a quick charge loss compensation to be determined for at least one block of memory; and

wherein the off-chip controller is configured to cause a wordline voltage of the memory to be adjusted according to the quick charge loss compensation;

wherein the off-chip controller being configured to cause a quick charge loss compensation to be determined comprises:

the off-chip controller being configured to cause at least a portion of a mini-array in the memory for each of the blocks of the memory to be programmed in accordance with a specific pattern;

the off-chip controller being configured to cause a first mean threshold voltage to be determined for the at least a portion of each mini-array;

the off-chip controller being configured to cause a difference to be determined between a second mean threshold voltage of the at least a portion of the mini-array upon reading a program block associated with the at least a portion of the mini-array and the first mean threshold voltage for the at least a portion of the mini-array; and

the off-chip controller being configured to cause a wordline voltage level to be adjusted by the difference.

14. An apparatus, comprising:

an off-chip controller;

wherein the off-chip controller is configured to cause a tracking block in a memory associated with at least one block of the memory to be programmed in accordance with a specific pattern;

wherein the off-chip controller is configured to cause a first mean threshold voltage for the tracking block to be determined;

wherein the off-chip controller is configured to cause the tracking block to be re-programmed in accordance with the specific pattern when its associated block is programmed; and

wherein the off-chip controller is configured to cause a wordline voltage level to be adjusted based on the first mean threshold voltage and a second mean threshold voltage for the tracking block after the reprogramming.

15. The apparatus of claim 14 ,

wherein the off-chip controller is configured to cause program blocks in the memory to be wear leveled; and

wherein the off-chip controller is configured to cause the tracking block to be erased when its associated block is erased.

16. The apparatus of claim 14 , wherein the off-chip controller being configured to cause a wordline voltage level to be adjusted comprises the off-chip controller being configured to cause the wordline voltage level to be adjusted equal to a difference between the first mean threshold voltage and the second mean threshold voltage for the tracking block after the re-programming.

17. The apparatus of claim 14 , wherein the tracking block is programmed as a single redundant memory block for one block of the memory.

18. The apparatus of claim 14 , wherein the tracking block is a plurality of mini-arrays, each block of the memory having a separate mini-array or a portion thereof associated therewith.

19. The apparatus of claim 18 , wherein the off-chip controller is configured to cause a mini-array margin search to be completed on the at least a portion of a mini-array block when its associated block is read.

20. The apparatus of claim 18 , wherein the off-chip controller is configured to cause contemporaneous programming of the at least a portion of a mini-array and its associated block.

Assignments (8)

Continuity (3)