Abstract:
A memory device implements a reading operation that comprises: providing first and second additional memory cells whose threshold voltage values correspond to a maximum value and a minimum value of a distribution of threshold voltages of a cell array of the memory device; programming the first and second additional memory cells with predetermined first and second logic values; simultaneously reading a logic contents of the first and second additional memory cells, and data to be read in the cell array; comparing the logic contents of the first and second additional memory cells, as read during the reading step, with the first and second predetermined logic values; generating a result signal of the comparison step, such a result signal having a first value in the event of the logic contents of the first and second additional memory cells, as read during the reading step, matching the first and second predetermined logic values, respectively, and having a second value in the event of the logic contents of the first and second additional memory cells, as read during the reading step, failing to match the first and second predetermined logic values, respectively.
Abstract:
Method for manufacturing an SOI wafer. On a monocrystalline silicon wafer, forming protective regions having the shape of an overturned U, made of an oxidation resistant material, the protective regions covering first wafer portions. Forming deep trenches in the wafer which extend between, and laterally delimit the first wafer portions, completely oxidizing the first wafer portions except their upper areas which are covered by the protective regions, to form at least one continuous region of covered oxide overlaid by the non-oxidized upper portions. Removing the protective regions, and epitaxially growing a crystalline semiconductor material layer from the non-oxidized upper portions.
Abstract:
A voltage regulator having a comparator with an output terminal that is the output of the regulator, terminals for connection to a voltage supply, a source of a reference voltage connected to an input terminal of the comparator, and a feedback circuit connected between the output terminal and the other input terminal of the comparator. To prevent transients upon the transition from the standby state to the active state, there is provided a second reference-voltage source that provides a reference voltage substantially equal to that of the first source, a switch for connecting the second source to the other input terminal of the comparator, and a control circuit that can activate the supply of the regulator and can close the switch for a predetermined period of time when the supply of the regulator is activated.
Abstract:
A semiconductor memory architecture having two memory banks each containing respective memory locations, and for each memory bank, respective circuits for selecting the locations of the bank and respective circuits for reading the data contained in the selected locations of the bank, a structure for the transfer of the data read by the reading circuits associated with the memory banks to data output terminals of the memory, there being a single data-transfer structure assigned selectively to one memory bank at a time and which includes storage for storing the most recent datum read by the reading circuits, and output driver circuits activated selectively in order to transfer the contents of the registers to the data output terminals of the memory, an addressing structure having, for each memory bank, and a respective circuit for the sequential scanning of the memory locations of the bank, operatively connected to the respective circuits for selecting the locations of the memory bank.
Abstract:
The device and method monitor the current delivered to a load through a power transistor including a sense transistor. The circuit includes a disturbances attenuating circuit that has a differential stage, and first, second and third stages referenced to ground, the respective input nodes of which are connected in common to an output node of the differential stage. The third stage is formed by a transistor identical to a transistor of the first stage and delivers a current signal through a current terminal thereof, proportional to the current being delivered to the load.
Abstract:
A structure for a semiconductor resistive element, applicable in particular to power components, having a high concentration substrate of the n type, a first epitaxial layer of the n type, a region of the p type arranged on said first epitaxial layer so to form the resistive element proper, a second epitaxial layer of n type grown on said first epitaxial layer to make the region of the p type a buried region, and an additional layer of the n type with a higher concentration with respect to the second epitaxial level, positioned on the embedded region. Low resistivity regions of the p type adapted to make low resistivity deep contacts for the resistor are provided. The buried region can be made either with a development that is substantially uniform in its main direction of extension or so to present, at on part of its length, a structure of adjacent subregions in marginal continuity. In this way, either a resistive element presenting a substantially linear performance in all ranges of applied voltage or a resistive element presenting a marked increase of the resistance value as the applied voltage increases can be made. This all with the additional possibility of selectively varying the resistance value demonstrated before the increase.
Abstract:
The multilevel memory device has a memory section containing cells that can be programmed with a predetermined number of levels greater than two, i.e., a multilevel array, and a memory section containing cells that can be programmed with two levels, i.e., a bilevel array. The multilevel array is used for storing high-density data, for which speed of reading is not essential, for example for storing the operation code of the system including the memory device. On the other hand, the bilevel array is used for storing data for which high speed and reliability of reading is essential, such as the BIOS of personal computers, and the data to be stored in a cache memory. The circuitry parts dedicated to programming, writing of test instructions, and all the functions necessary for the operation of the memory device, can be common to both arrays.
Abstract:
A voltage/current controller device, particularly for interleaving switching regulators, comprises: a DC/DC converter having a plurality of modules, with each module including a drive transistor pair connected in series between first and second supply voltage references, a current sensor connected to one transistor in the pair, and a current read circuit connected to the sensor. Advantageously, the read circuit comprises a transconductance amplifier connected across the current sensor to sense a voltage signal related to a load current being applied to each module, the transconductance amplifier reading the voltage signal with the transistor in the conducting state.
Abstract:
Disclosed is a bootstrap circuit in DC/DC static converters having the characteristic of comprising a fixed frequency signal, a recharge circuit of a capacitor and current generator means, said generator means controlled so as to emit current pulses, in synchrony with said fixed frequency signal, of a predetermined duration, every time that charge accumulated by said capacitor goes below a predetermined level.
Abstract:
A circuit extends the output voltage range of an integrator circuit wherein the input signal is used to produce an output signal, and the voltage of the output signal develops monotonically within a predetermined range of possible values. The integrator circuit is driven within an integration time period such that each time the signal at its output reaches a limit of the range of values, the integrator circuit starts a subsequent integration stage of the input signal in which the output signal develops again within the above-mentioned range. This takes place by resetting the integrator circuit or by a reversal of the characteristic slope of the output signal. This is combined with storing the number of occasions on which these interventions have occurred as determined by a counter. This enables the actual voltage value of the signal resulting from the integration to be calculated by a relatively straightforward mathematical operation from the reading of the counter, and from the signal currently present at the output of the integrator at the end of the integration period.