Method for reading a multilevel nonvolatile memory and multilevel nonvolatile memory

摘要

The sensing circuits comparing the current flowing in the cell with a plurality of reference currents are not identical to each other but differently amplify the compared currents. In particular, the sensing circuit associated with the lowest reference current amplifies the cell current more than the other sensing circuits and to the respective reference current. The current dynamics is thereby increased and it is possible to keep the reading voltage low, since the inherent characteristic of the lowest reference current may be very close to or directly superimposed on that of the immediately preceding memory cell current distribution, retaining the possibility of discriminating between the different logic levels.