Methods of calculating compensation voltage and adjusting threshold voltage and memory apparatus and controller

A method of calculating a compensation voltage, adaptable to a rewritable non-volatile memory, wherein the rewritable non-volatile memory has a plurality of word lines, each of the word lines has a plurality of pages, the rewritable non-volatile memory comprises a plurality of storage states, the storage states comprise at least a first storage state and a second storage state, and voltage ranges of the first storage state and the second storage state are distinguished by a threshold voltage, the method comprising:

• when an error bit number produced by one of the pages is greater than a first predetermined value, locating a plurality of error bit positions in the page having the error bit number greater than the first predetermined value;
• reading a plurality of corresponding data from the error bit positions;
• obtaining a first error bit number by counting the number of bits that is written in the first storage state and read in the second storage state;
• obtaining a second error bit number by counting the number of bits that is written in the second storage state and read in the first storage state;
• and
• calculating the compensation voltage according to the first error bit number and the second error bit number.

A rewritable non-volatile memory apparatus, comprising:

• a rewritable non-volatile memory;
• a connector, for receiving data;
• and
• a memory controller, coupled to the rewritable non-volatile memory and the connector, for executing at least following steps:
• writing the data into the rewritable non-volatile memory;
• reading the data from the rewritable non-volatile memory, wherein the data is at least corresponding to one of a plurality of storage states of the rewritable non-volatile memory, and voltage ranges of the storage states are distinguished by at least one threshold voltage;
• comparing the read data with the written data to obtain an error bit information;
• calculating a compensation voltage of the threshold voltage according to the error bit information;
• and
• adjusting the threshold voltage according to the compensation voltage.

A memory controller, for managing a rewritable non-volatile memory, wherein the rewritable non-volatile memory has a plurality of physical blocks, each of the physical blocks has a plurality of pages, and the pages corresponding to the same physical block are written individually and erased all together, the memory controller comprising:

• a memory management circuit;
• a memory interface, coupled to the memory management circuit, for coupling to the rewritable non-volatile memory;
• and
• a host interface, coupled to the memory management circuit, for receiving data;
• wherein the memory management circuit executes at least following steps:
• writing the data into the rewritable non-volatile memory;
• reading the data from the rewritable non-volatile memory, wherein the data is at least corresponding to one of a plurality of storage states of the rewritable non-volatile memory, and voltage ranges of the storage states are distinguished by at least one threshold voltage;
• comparing the read data with the written data to obtain an error bit information;
• calculating a compensation voltage of the threshold voltage according to the error bit information;
• and
• adjusting the threshold voltage according to the compensation voltage.