Patent attributes
A memory device to calibrate voltages used to read a group of memory cells. For example, the memory device measures first signal and noise characteristics of a group of memory cells by reading the group of memory cells at first test voltages that are separated from each other by a first voltage interval. An estimate of a read level of the group of memory cells is determined based on the first signal and noise characteristics. The memory device then measures second signal and noise characteristics of the group of memory cells by reading the group of memory cells at second test voltages that are separated from each other by a second voltage interval that is smaller than the first voltage interval. An optimized read voltage for the read level is computed from the second signal and noise characteristics.
