US 12,314,599 B2
Method for adjusting a read voltage level or log likelihood ratio of a memory based on a calculated bit change ratio, memory controlling circuit unit, and memory storage device
Yu-Siang Yang, New Taipei (TW); Wei Lin, Taipei (TW); Shih-Jia Zeng, Hsinchu (TW); An-Cheng Liu, Taipei (TW); and Yu-Cheng Hsu, Yilan County (TW)
Assigned to PHISON ELECTRONICS CORP., Miaoli (TW)
Filed by PHISON ELECTRONICS CORP., Miaoli (TW)
Filed on Jun. 2, 2021, as Appl. No. 17/336,347.
Claims priority of application No. 110117140 (TW), filed on May 12, 2021.
Prior Publication US 2022/0365706 A1, Nov. 17, 2022
Int. Cl. G06F 3/06 (2006.01)
CPC G06F 3/0655 (2013.01) [G06F 3/0604 (2013.01); G06F 3/0679 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A data accessing method for a rewritable non-volatile memory module, wherein the rewritable non-volatile memory module comprises a plurality of physical erasing units, each of the physical erasing units has a plurality of physical programming units, the data accessing method comprising:
receiving a write command and write data corresponding to the write command from a host system;
programming first data to a physical programming unit among the physical programming units, wherein the first data comprises the write data, an error checking and correcting code for detecting an error in the write data, and dummy data not used in a decoding operation for detecting the error in the write data based on the error checking and correcting code, wherein bit values of all bits in the dummy data comprised in the first data are all the same;
reading a codeword from the physical programming unit;
obtaining a total number of at least one first bit in the dummy data comprised in the codeword, wherein a bit value of each of the at least one first bit is different from a bit value of each of at least one second bit in the dummy data comprised in the codeword;
obtaining a bit change ratio according to the total number, wherein the total number is positively correlated to the bit change ratio;
adjusting a read voltage level or a log likelihood ratio according to the bit change ratio; and
performing the decoding operation on the codeword by using the adjusted read voltage level or the adjusted log likelihood ratio.