Read voltage control method, memory storage device and memory control circuit unit

A memory storage device, comprising:

• a connection interface unit configured to couple to a host system;
• a rewritable non-volatile memory module comprising a plurality of memory cells;
• and
• a memory control circuit unit, coupled to the connection interface unit and the rewritable non-volatile memory module,
• wherein the memory control circuit unit is configured to send a first read command sequence which instructs a reading of a plurality of first memory cells in the memory cells by using a first voltage level to obtain first data, wherein the first data is a total number of memory cells turned on by the first voltage level in the first memory cells,
• the memory control circuit unit is further configured to determine a channel parameter according to curve information of a threshold voltage distribution of the first memory cells, wherein the curve information describes at least one of a curve endpoint, a curve type, a curve peak value and a curve slope of the threshold voltage distribution, and the threshold voltage distribution presents a number of memory cells each having a specific threshold voltage among the first memory cells;
• the memory control circuit unit is further configured to obtain first adjustment information of a read voltage according to the first data and the channel parameter of the first memory cells, the channel parameter reflects a channel status of the first memory cells, and
• the memory control circuit unit is further configured to adjust a voltage level of the read voltage from the first voltage level to a second voltage level according to the first adjustment information.

A memory control circuit unit for controlling a rewritable non-volatile memory module, the memory control circuit unit comprising:

• a host interface, configured to couple to a host system,
• a memory interface, configured to couple to a rewritable non-volatile memory module, wherein the rewritable non-volatile memory module comprises a plurality of memory cells;
• and
• a memory management circuit, coupled to the host interface and the memory interface,
• wherein the memory management circuit is configured to send a first read command sequence which instructs a reading of a plurality of first memory cells in the memory cells by using a first voltage level to obtain first data, wherein the first data is a total number of memory cells turned on by the first voltage level in the first memory cells,
• the memory management circuit is further configured to determine a channel parameter according to curve information of a threshold voltage distribution of the first memory cells, wherein the curve information describes at least one of a curve endpoint, a curve type, a curve peak value and a curve slope of the threshold voltage distribution, and the threshold voltage distribution presents a number of memory cells each having a specific threshold voltage among the first memory cells;
• the memory management circuit is further configured to obtain first adjustment information of a read voltage according to the first data and the channel parameter of the first memory cells, the channel parameter reflects a channel status of the first memory cells, and
• the memory management circuit is further configured to adjust a voltage level of the read voltage from the first voltage level to a second voltage level according to the first adjustment information.