Method for operating non-volatile memory device and memory controller
First Claim
1. A method of operating a non-volatile memory device, the method comprising:
- employing a voltage generator to apply first and second read voltages to a first word line of the memory device to perform a read operation;
counting first memory cells of the memory device each having a threshold voltage belonging to a first voltage range between the first read voltage and the second read voltage;
employing the voltage generator to apply a third read voltage to the first word line sequentially after applying the second read voltage to count second memory cells of the memory device each having a threshold voltage belonging to a second voltage range between the second read voltage and the third read voltage;
comparing a number of the first memory cells counted and a number of the second memory cells counted;
determining a fourth read voltage based on a result of the comparing; and
employing the voltage generator to apply the fourth read voltage to the first word line sequentially after applying the third read voltage.
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Accused Products
Abstract
An operating method for a non-volatile memory device includes applying first and second read voltages to a first word line to perform a read operation; counting first memory cells each having a threshold voltage belonging to a first voltage range between the first read voltage and the second read voltage; applying a third read voltage to the first word line sequentially after applying the second read voltage to count second memory cells each having a second threshold voltage belonging to a voltage range between the second read voltage and the third read voltage; comparing the number of first memory cells counted and the number of second memory cells counted; determining a fourth read voltage based on a result of the comparing; and applying the fourth read voltage to the first word line sequentially after applying the third read voltage.
245 Citations
18 Claims
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1. A method of operating a non-volatile memory device, the method comprising:
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employing a voltage generator to apply first and second read voltages to a first word line of the memory device to perform a read operation; counting first memory cells of the memory device each having a threshold voltage belonging to a first voltage range between the first read voltage and the second read voltage; employing the voltage generator to apply a third read voltage to the first word line sequentially after applying the second read voltage to count second memory cells of the memory device each having a threshold voltage belonging to a second voltage range between the second read voltage and the third read voltage; comparing a number of the first memory cells counted and a number of the second memory cells counted; determining a fourth read voltage based on a result of the comparing; and employing the voltage generator to apply the fourth read voltage to the first word line sequentially after applying the third read voltage. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A method of controlling a memory device, the method comprising:
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counting first memory cells of the memory device each having a threshold voltage belonging to a first voltage range between a first read voltage and a second read voltage; counting second memory cells of the memory device each having a threshold voltage belonging to a second voltage range between the second read voltage and a third read voltage; comparing a number of the first memory cells counted and a number of the second memory cells counted; and determining a fourth read voltage to be applied to memory cells of the memory device sequentially after the third read voltage based on a comparison result. - View Dependent Claims (9, 10, 11, 12, 13)
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14. A method, comprising:
- counting first memory cells of a memory device each having a threshold voltage belonging to a first voltage range between a first read voltage and a second read voltage;
counting second memory cells of the memory device each having a threshold voltage belonging to a second voltage range between the second read voltage and a third read voltage; comparing a number of the first memory cells counted and a number of the second memory cells counted to produce a comparison result; and determining, based on the comparison result, a third voltage range for counting memory cells of the memory device having a threshold voltage belonging to the third voltage range. - View Dependent Claims (15, 16, 17, 18)
- counting first memory cells of a memory device each having a threshold voltage belonging to a first voltage range between a first read voltage and a second read voltage;
Specification