| 摘要 |
Phase-change memory (PCM) cells store data using alloy resistors in high-resistance amorphous and low-resistance crystalline states. The time of the memory cell's set-current pulse can be 100 ns, much longer than read or reset times. The write time thus depends on the write data. The very long write-1 time may require wait states. To eliminate wait states for sequential accesses, the PCM cells are divided into 16 banks. Each bank has its own bank write latch that stores data locally at the bank while the bank is being written. Data lines to the banks are freed up to transfer data to other banks once the data is written into the local bank write latch, allowing the long set-current pulse to be applied locally to slowly grow crystals in the alloy resistors. External host data are buffered and applied to the data lines by an array data mux.
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