Dynamic Tuning Of First Read Countermeasures
AssigneeSanDisk Technologies LLC
InventorsLiang Pang, Yingda Dong, Jiahui Yuan, Charles Kwong
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AssigneeSanDisk Technologies LLC
InventorsLiang Pang, Yingda Dong, Jiahui Yuan, Charles Kwong
Estimating the term…
Techniques are provided for improving the accuracy of read operations of memory cells, where the threshold voltage (Vth) of a memory cell can shift depending on when the read operation occurs. Countermeasures are provided for a first read situation in which a memory is read after a power on event or after a long delay since a last read. Read voltages of lower or higher programmed data states are set according to a positive or negative temperature coefficient (Tco), respectively. Read voltages for error recovery can be set similarly. In another aspect, a wait period between a dummy voltage and a read voltage is a function of temperature. In another aspect, word line voltages of unselected blocks are set according to a negative Tco. In another aspect, pass voltages are set based on a Tco for each programmed data state.
An apparatus, comprising:
A method, comprising:
An apparatus, comprising:
Dependencies are inferred from the claim text.