REFRESH SCHEME FOR MEMORY CELLS WITH NEXT BIT TABLE

摘要

The memory refresh control scheme allows flexible internal refresh rates based on the external 1X refresh rate and allows skipping the refresh cycle for the strong memory rows based on the external 1X refresh rate. The memory controller performs a memory refresh by reading the refresh address from the refresh address counter, reading the weak address from the weak address table, and generating the next weakest address value based at least in part on the next bit sequence associated with the weak address do. The memory controller compares the refresh address with the weak address and the next weakest address value. Based on the comparison, the memory controller selects between skipping the refresh cycle, refreshing the refresh address, refreshing the weak address, and refreshing both the refresh address and the weak address.