Variable fast look neighbor ahead to improve read accuracy

A controller in communication with a memory apparatus including memory cells each connected to one of a plurality of word lines and configured to retain a threshold voltage corresponding to one of a plurality of data states, the controller configured to:

• instruct the memory apparatus to determine ones of the plurality of data states for memory cells of a neighboring word line of the plurality of word lines adjacent to a selected word line of the plurality of word lines in a pre-read;
• instruct the memory apparatus to determine an adjusted sense time according to a first zone and a second zone of a plurality of zones identified for the memory cells of the neighboring word line adjacent each of the memory cells of the selected word line and the one of the plurality of data states targeted for the memory cells of the selected word line and a temperature of the memory apparatus;
• instruct the memory apparatus to select a first zone sense coefficient and a first zone temperature coefficient and a second zone sense coefficient and a second zone temperature coefficient from a coefficient lookup table based on the one of the plurality of data states targeted for the memory cells of the selected word line,
• instruct the memory apparatus to calculate a first zone delta sense time using the first zone sense coefficient and the temperature of the memory apparatus and calculate a second zone delta sense time using the second zone sense coefficient and the temperature of the memory apparatus,
• instruct the memory apparatus to determine the adjusted sense time for each one of the memory cells of the selected word line using the first zone delta sense time in response to the one of the plurality of zones identified being the first zone and determine the adjusted sense time for each one of the memory cells of the selected word line using the second zone delta sense time in response to the one of the plurality of zones identified being the second zone, and
• instruct the memory apparatus to perform a plurality of reads on the selected word line for each of a plurality of groupings of ones of the plurality of data states in a read operation using the adjusted sense time determined for each of the memory cells of the selected word line.

A method of operating a memory apparatus including memory cells each connected to one of a plurality of word lines and configured to retain a threshold voltage corresponding to one of a plurality of data states, the method comprising:

• determining ones of the plurality of data states for memory cells of a neighboring word line of the plurality of word lines adjacent to a selected word line of the plurality of word lines in a pre-read;
• determining an adjusted sense time according to a first zone and a second zone of a plurality of zones identified for the memory cells of the neighboring word line adjacent each of the memory cells of the selected word line and the one of the plurality of data states targeted for the memory cells of the selected word line and a temperature of the memory apparatus;
• selecting a first zone sense coefficient and a first zone temperature coefficient and a second zone sense coefficient and a second zone temperature coefficient from a coefficient look up table based on the one of the plurality of data states targeted for the memory cells of the selected word line;
• calculating a first zone delta sense time using the first zone sense coefficient and the temperature of the memory apparatus and calculate a second zone delta sense time using the second zone sense coefficient and the temperature of the memory apparatus;
• determining the adjusted sense time for each one of the memory cells of the selected word line using the first zone delta sense time in response to the one of the plurality of zones identified being the first zone and determine the adjusted sense time for each one of the memory cells of the selected word line using the second zone delta sense time in response to the one of the plurality of zones identified being the second zone;
• and
• performing a plurality of reads on the selected word line for each of a plurality of groupings of ones of the plurality of data states in a read operation using the adjusted sense time determined for each of the memory cells of the selected word line.