Patent ID: 9576672
Date: 2017-02-21
CPC Classifications: G11C

Claim:
1. A storage device, comprising: a nonvolatile memory device; and a memory controller configured to selectively transmit one of a page read command with a first address and a partial page read command with a second address to the nonvolatile memory device, in response to a read request from a host, wherein: the nonvolatile memory device performs a first read operation in response to the page read command with the first address, or performs a second read operation in response to the partial page read command with the second address, a number of selected memory cells of the second read operation is smaller than a number of selected memory cells of the first read operation, a time required to perform the first read operation is longer than a time required to perform the second read operation, each of the first address and the second address corresponds to the same row, a first read voltage and a second read voltage are applied to a word line of the selected memory cells during the first read operation to discriminate at least one data state, and at least one memory cell identified as an off cell by the first read voltage is sensed during a sensing operation using the second read voltage.