Flash Memory Read Method Using Conditional Threshold Voltage Adjustment

The patent applies partial action by performing multiple read operations only when necessary - specifically when the first read operation with initial threshold voltage yields an uncorrectable error after hard decoding. The system selectively executes second and third read operations with adjusted threshold voltages only in error cases, rather than always performing all reads, thus balancing reliability improvement with time consumption.

The reading process is segmented into distinct stages: first read operation with initial threshold voltage, hard decoding attempt, conditional second read operation with increased threshold voltage, and conditional third read operation with decreased threshold voltage. This segmentation allows the system to progress through reading steps only as needed, improving efficiency by avoiding unnecessary operations.

The patent implements dynamic threshold voltage adjustment based on error detection results. The reading process adapts by modifying threshold voltages in subsequent operations only when errors are detected, creating a dynamic response to actual memory cell states rather than using fixed threshold sequences. This dynamic approach reduces unnecessary complexity while maintaining precision.

The system employs feedback mechanisms where hard decoding results from the first read operation determine whether subsequent read operations with different threshold voltages should be executed. The feedback loop (read → decode → detect error → adjust threshold → re-read) enables precision improvement while managing complexity through conditional execution based on actual error conditions.