Abstract: A current source including a current mirror circuit and an active load circuit which form a reference branch, for setting a reference current value, and a mirroring branch, defining an output current value, connected between supply and ground. A voltage stabilizing transistor is interposed between the current mirror circuit and the load circuit in the reference branch only, and is so biased as to maintain its gate terminal at a predetermined voltage. As such, the potential with respect to ground of the drain terminal of the reference branch load transistor is fixed, so that its drain-source voltage drop (and the current through it) is substantially independent of supply voltage. The current source may be used to advantage in an oscillator for generating the: clock signal of a nonvolatile memory.

Abstract: An anti-logarithmic type converter circuit, with temperature compensation, includes a diode connected between a unity gain, non-inverting interface circuit and a low-impedance reference voltage circuit. A thermal compensation circuit is connected between the converter input and the interface circuit. The thermal compensation circuit includes current mirror circuits having a gain higher than one and their output currents linearly dependent on temperature.

Abstract: A process for forming low threshold voltage P-channel MOS transistors in semiconductor integrated circuits for analog applications, said circuits including high resistivity resistors formed in a layer of polycrystalline silicon and N-channel MOS transistors having active areas which have been obtained by implantation in a P-type well, comprises the steps of,providing a first mask over both said resistors and the semiconductor regions where the low threshold voltage P-channel transistors are to be formed,doping the polycrystalline layer uncovered by said first mask,--providing a second mask for protecting the resistors and the semiconductor regions where said low threshold voltage P-channel transistors are to be formed, andN+ implanting the active areas of the N-channel transistors.

Abstract: A circuit comprises a section generating a pulse signal for asynchronously enabling the read phases; a section generating precharge and detecting signals of adjustable duration, for controlling data reading from the memory and data supply to the output buffers; a section generating a noise suppressing signal for freezing the data in the output buffers during loading into the output circuits, and the duration of which is exactly equal to the propagation time of the data to the output circuits of the memory, as determined by propagating a data simulating signal in an output simulation circuit; a section generating a loading signal, the duration of which may be equal to that of the noise suppressing signal or extended by an extension circuit in the event the array presents slower elements which may thus be read; and a section generating a circuit reset signal.

Abstract: A circuit device for recovering energy from an inductive load is connected to a protection circuit for protecting a driver circuit from a charge contained in the inductive load. The inductive load is connected between a power supply line at one end and the driver circuit and protection circuit at another end. The circuit device has a charge accumulator, preferably a capacitor, connected to the protection circuit for accumulating charge from the inductive load. A control circuit monitors the level of charge in the capacitor. A switch, connected between the capacitor and the power supply line, permits the charge accumulated in the capacitor to discharge into the power supply line. The control circuit controls the switch so as to permit the intermittent discharge of the inductive load: the switch is opened to permit charge from the inductive load to accumulate in the capacitor; and, the switch is closed to permit the capacitor to discharge the accumulated charge to the power supply line.

Abstract: A structure of an electronic device having a predetermined unidirectional conduction threshold is formed on a chip of an N-type semiconductor material and includes a plurality of isolated N-type regions. Each isolated N-type region is bounded laterally by an isolating region and at the bottom by buried P-type and N-type regions which form in combination a junction with a predetermined reverse conduction threshold and means of connecting the junctions of the various isolated regions serially together. The buried N-type region of the first junction in the series is connected to a common electrode, which also is one terminal of the device, over an internal path of the N-type material of the chip, and the buried P-type region of the last junction in the series contains an additional buried N-type region which is connected electrically to a second terminal of the device.

Abstract: A load timing circuit including an output simulation circuit similar to the output circuits of the memory, so as to present the same propagation delay; a simulating signal source for generating a data simulating signal; a synchronizing network for detecting a predetermined switching edge of the data simulating signal and enabling supply of the signal to the output simulation circuit and data supply to the output circuits of the memory; a combinatorial network for detecting propagation of the data simulating signal to the output of the output simulation circuit and disabling the data simulating signal; and a reset element for resetting the timing circuit.

Abstract: A method and apparatus for retaining a catheter tip in a fixed position within a blood flow and preventing it from contacting a blood vessel wall. The apparatus includes a tip retainer at the distal end of the catheter that anchors the tip of the catheter within the blood vessel. The catheter tip is retained within the blood vessel spaced from the wall to ensure that it does not contact the wall of the blood vessel. This reduces damage to the blood vessel caused by chronic movement and contact between the catheter tip and the wall of the blood vessel. In one embodiment, the tip retainer includes a prong that penetrates the wall of the blood vessel, thus preventing the catheter tip from moving longitudinally within the blood vessel. In alternative embodiments, the tip retainer contacts the wall but does not penetrate the wall.

Abstract: A method of manufacture of a low-capacitance programmed cell structure for read-only memory circuits comprises a field-effect transistor having conventional source and drain regions separated by a channel region overlaid by the gate of the transistor. This ROM memory cell is programmed by a channel implant extending only from the source region for a selected distance into the channel region.

Abstract: A process for the manufacture of an integrated voltage limiter and stabilizer component in a flash EEPROM memory device comprises a step of formation of an N type lightly doped well on a single-crystal silicon substrate; a step of formation of an active area on the surface of said N type well; a step of growth of a thin gate oxide layer over said active area; a step of implantation of a first heavy dose of N type dopant into said N type well to obtain an N type region; a step of implantation of a second heavy dose, higher than said first heavy dose, of N type dopant into said N type region to obtain an N+ contact region to both the N type well and said N type region; a step of implantation of a third heavy dose, higher than said first heavy dose, of P type dopant into said N type region to form a P+ region.

Abstract: The process provides for the simultaneous N+ type implantation of areas of a semiconductor substrate of type P for the formation of a control gate and of highly doped regions of source and drain, defining a channel region. After oxide growth there is executed the deposition and the definition of a polysilicon layer, one region of which constitutes a floating gate above the control gate and the channel region and partially superimposed over the regions of source and drain.

Abstract: There is described a semiconductor memory including a matrix of rows and columns of memory cells, wherein the columns are grouped together in sectors, each sector representing the portion of the matrix itself related to a data input/output line. Each sector is in turn divided into packets of columns, and there are redundancy columns suitable for replacing a matrix column containing defective memory cells. Each of the redundancy columns is included in a respective packet. The memory also includes control circuits to execute the abovementioned replacement.

Abstract: A method comprising the steps of depositing a first and second polysilicon layer, separated by an oxide layer; selectively etching the second polysilicon layer to form first gate regions; forming first substrate regions in the substrate and laterally in relation to the first gate regions; selectively etching the first polysilicon layer to form second gate regions of a length greater than the first gate regions; and forming in the substrate, laterally in relation to the second gate regions and partially overlapping the first substrate regions, second substrate regions of a higher doping level than the first substrate regions.