Refresh scheme for memory cells with next bit table
First Claim
1. A memory refresh method within a memory controller, comprising:
- reading a refresh address from a refresh address counter;
reading a weak address from a weak address table;
generating a next weak address value based at least in part on a next bit sequence combined with the weak address;
comparing the refresh address to the weak address and to the next weak address value; and
selecting between skipping a refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address based at least in part on the comparing.
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Accused Products
Abstract
A memory refresh control technique allows flexible internal refresh rates based on an external 1× refresh rate and allows skipping a refresh cycle for strong memory rows based on the external 1× refresh rate. A memory controller performs a memory refresh by reading a refresh address from a refresh address counter, reading a weak address from a weak address table and generating a next weak address value based at least in part on a next bit sequence combined with the weak address. The memory controller compares the refresh address to the weak address and to the next weak address value. Based on the comparison, the memory controller selects between skipping a refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address.
8 Citations
20 Claims
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1. A memory refresh method within a memory controller, comprising:
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reading a refresh address from a refresh address counter; reading a weak address from a weak address table; generating a next weak address value based at least in part on a next bit sequence combined with the weak address; comparing the refresh address to the weak address and to the next weak address value; and selecting between skipping a refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address based at least in part on the comparing. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A memory refresh apparatus, comprising:
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a refresh counter operable to store a refresh address; a weak address table operable to store a weak address; a next bit table operable to generate a next weak address based at least in part on next bit values in the next bit table combined with the weak address; and a refresh controller operable to select between skipping a refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address based at least in part on comparing the refresh address to the weak address and to the next weak address. - View Dependent Claims (9, 10, 11, 12, 13, 14)
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15. A memory controller apparatus, comprising:
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a refresh counter to store a refresh address; a weak address table to store a weak address; a next bit table to generate a next weak address based at least in part on next bit values in the next bit table combined with the weak address; and means for selecting between skipping a refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address based at least in part on comparing the refresh address to the weak address and to the next weak address. - View Dependent Claims (16, 17, 18)
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19. A computer program product for a memory refresh comprising:
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a non-transitory computer-readable medium having program code recorded thereon, the program code comprising; program code to store a refresh address in a refresh counter; program code to store a weak address in a weak address table; program code to generate a next weak address based at least in part on next bit values in a next bit table combined with the weak address; and program code to select between skipping a refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address based at least in part on comparing the refresh address to the weak address and to the next weak address. - View Dependent Claims (20)
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Specification