Abstract: A telephone subscriber circuit is coupled via a single galvanic isolation element to provide, from a subscriber apparatus unconnected to the telephone line, on- and off-hook signals to the telephone line and to control transfer of telephonic signals between the subscriber apparatus and the telephone line. The galvanic isolation element is a photocoupler. The subscriber circuit includes a speech circuit coupled to the line through a diode bridge circuit and an electronic switch is connected between the speech circuit and the diode bridge circuit. An input terminal of the speech circuit and a control terminal of the electronic switch are each connected through a voltage-generating circuit and level-translating circuit to an output terminal of the galvanic isolation element.

Abstract: An electro-luminescent material and solid state electro-luminescent device comprising a mixed material layer formed of a mixture of silicon and silicon oxide doped with rare earth ions so as to show intense room-temperature photo- and electro-luminescence is described. The luminescence is due to internal transitions of the rare earth ions. The mixed material layer has an oxygen content ranging from 1 to 65 atomic % and is produced by vapor deposition and rare earth ions implant. A separated implant with elements of the V or III column of the periodic table of elements gives rise to a PN junction. The so obtained structure is then subjected to thermal treatment in the range 400.degree.-1100.degree. C.

Abstract: A bistable logic network of the sequential type, responsive to the edges of input signals, comprising first and second input SR flip-flops which are connected to an output SR flip-flop through two transfer and block logic gates.Each of said logic gates has two input terminals connected to the output terminal and to one input terminal of an input flip-flop.The output terminals of the output flip-flop are feedback connected to the other input terminals of the two input flip-flops.

Abstract: An electronic device for the automatic conversion of sampling frequencies, being a type adapted to convert a predetermined frequency of a sampled input signal to a desired frequency of an output signal. The device is comprised of:a phase detector being input both the input frequency and the output frequency; a decoder block associated with the detector to determine an interpolation coefficient; an interpolation filter having a digital input for encoding the sampling signal and receiving the input frequency on the one side, and a digital signal representative of the interpolation coefficient on the other side; and a synchronizer connected after the filter and being input both said input and output frequencies, the synchronizer having a digital output for encoding the converted sampling signal.

Abstract: An electro-luminescent material and solid state electro-luminescent device comprising a mixed material layer formed of a mixture of silicon and silicon oxide doped with rare earth ions so as to show intense room-temperature photo- and electro-luminescence is described. The luminescence is due to internal transitions of the rare earth ions. The mixed material layer has an oxygen content ranging from 1 to 65 atomic % and is produced by vapor deposition and rare earth ions implant. A separated implant with elements of the V or III column of the periodic table of elements gives rise to a PN junction. The so obtained structure is then subjected to thermal treatment in the range 400.degree.-1100.degree. C.

Abstract: A high-voltage resistor integrated on a semiconductor substrate with opposite sign conductivity, and being of a type with one end connected to the substrate and another end connected to a lower electric potential than the substrate, further comprises at least one thin layer of the field plate type covering at least a section of the resistor.