摘要 |
A flash memory array includes a reference bit line on which a reference current is imposed. During read operation, bit lines selected for reading are connected to current-to-voltage converters, each of which generates an output voltage based upon the input current flowing in the bit line. The output voltage of the current-to-voltage converter is compared to a reference voltage derived from the output of a reference current-to-voltage converter whose input is driven by a reference current on a reference bit line. Any cell that conducts more current than the reference current will be regarded as an erased cell. Conversely, any cell that conducts less current than the reference current will be regarded as a programmed cell.
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