Abstract: A circuit structure for reading data contained in an electrically programmable/erasable integrated non-volatile memory device includes a matrix of memory cells and at least one reference cell for comparison with a memory cell during a reading phase. The reference cell is incorporated in a reference cells sub-matrix which is structurally independent of the matrix of memory cells. Also provided is a conduction path between the matrix and the sub-matrix, which path includes bit lines of the sub-matrix of reference cells extended continuously into the matrix of memory cells.

Abstract: 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.

Abstract: The integrated device comprises a PMOS transistor and a voltage selector having an output connected to the bulk terminal of the PMOS transistor. The voltage selector comprises an input stage supplying a supply voltage or a programming voltage according to whether the device is in a reading step or in a programming step; a comparator connected to the output of the input stage, receiving a boosted voltage, and generating a first control signal, the state whereof depends upon the comparison of the voltages at the inputs of the comparator; a logic circuit connected to the output of the comparator and generating a second control signal, the state whereof depends upon the state of the first control signal and of a third-level signal; and a switching circuit controlled by the first control signal, by the second control signal, and by the third-level signal and supplying each time the highest among the supply voltage, the boosted voltage, and the programming voltage.

Abstract: A charge pump having a phase-generator circuit generating phase signals and an oscillator circuit supplying a clock signal, a current-limitation circuit to limit the current flowing in the oscillator circuit, and a control circuit supplying on an output a control signal supplied to the current-limitation circuit. The control circuit has a first current mirror connected to a ground line, a second current mirror connected to a supply line, a cascode structure arranged between the first and the second current mirrors and connected to the output of the control circuit to compensate the effects on the control signal caused by sharp relative variations between the potential of the supply line and the potential of the ground line, and a compensation circuit to compensate the effects on the control signal caused by sharp relative variations between the potential of the supply line and the potential of the ground line and by slow variations in temperature.

Abstract: A voltage boosting device for speeding power-up of multilevel nonvolatile memories, including a voltage regulator and a charge pump and having an output terminal; the voltage regulator having a regulation terminal connected to the output terminal, and an output supplying a control voltage; the read charge pump having an output connected to the output terminal and supplying a read voltage. The device further includes an enable circuit connected to the output and having a pump enable output connected to a charge pump enable terminal and supplying a pump enable signal. The pump enable signal is set at a first logic level so as to activate the charge pump when the read voltage is lower than a nominal value. In addition, the device generates a power-up sync signal which activates a read operation when the read voltage reaches its nominal value and a chip enable signal is set at an active value.