Patent ID: 11923028
Assignee: nan
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A method, comprising:
collecting pre-decoding state information for a read reference voltage by reading data stored in a non-volatile storage device using the read reference voltage;
collecting post-decoding state information for the read reference voltage after decoding the data;
obtaining a first probability of state error for a first state and a second probability of state error for a second state under the read reference voltage, wherein the first state and the second state are two adjacent states distinguished by the read reference voltage, the pre-decoding state information and the post-decoding state information include how many cells are in the first state before and after the decoding, how many cells are in the second state before and after the decoding, how many cells in the first state before the decoding are corrected to the second state after the decoding and how many cells in the second state before the decoding are corrected to the first state after the decoding, the first probability of state error is equal to a number of cells in the second state before the decoding corrected to the first state after the decoding divided by a total number of cells in the first state after the decoding, and the second probability of state error is equal to a number of cells in the first state before the decoding corrected to the second state after the decoding divided by a total number of cells in the second state after the decoding;
generating a comparison of probabilities of state error for the read reference voltage by comparing the first probability of state error to the second probability of state error;
obtaining an adjustment amount to the read reference voltage based on the comparison of probabilities of state error; and
adjusting the read reference voltage by applying the adjustment amount to the read reference voltage to obtain an adjusted read reference voltage,
wherein the comparison of probabilities of state error is a wrong state ratio and obtaining the adjustment amount to the read reference voltage is further based on the read reference voltage.