Circuital structure for programming data in a non-volatile memory device

摘要

A circuit structure for programming data in reference cells of an electrically programmable/erasable integrated non-volatile memory device includes a matrix of multi-level memory cells and a corresponding reference cell provided for comparison with a respective memory cell during the read phase. The reference cell is incorporated, along with other cells of the same type, in a reference cell sub-matrix which is structurally independent of the memory cell matrix and directly accessed from outside in the DMA mode. The bit lines of the sub-matrix branch off to a series of switches which are individually operated by respective control signals REF(i) issued from a logic circuit with the purpose of selectively connecting the bit lines to a single external I/O terminal through a single addressing line of the access DMA mode.