Abstract: For the generation of a junction voltage with a negative temperature coefficient, a band gap reference circuit includes a first semiconductor element (T) and a voltage divider (R3, R4) adapted to generate a measure of the junction voltage across a main current path of a second semiconductor element (T5), a current source (J1) being adapted to generate a reference current with a positive temperature coefficient by means of a resistive element (R1) coupled in series with the main current path. Since the reference current generates a compensation voltage with a positive temperature coefficient across the resistive element (R1) the sum of the measure of the junction voltage and the compensation voltage yields a reference voltage with a specific temperature coefficient, the presence of the voltage divider (R3, R4) inter alia enabling a reference voltage with a temperature coefficient of zero volts per temperature unit to be obtained at comparatively low supply voltages.

Abstract: This method of processing data protected by encryption is particularly suitable for smart cards utilizing the DES system. The method enables the execution of the irregular permutation of the key on the basis of a correspondence table, which operation is most costly as regards processing time and code length in the cited system. The method involves the decomposition of the initial permutation into a plurality of elementary permutations so that the majority thereof is performed on at least two bits, the bits of the various octets of the key being marked, a masking system being applied in order to extract the appropriate bits for their permutation in the positions predetermined by the correspondence table.

Abstract: A method of rotating a word constituted by binary elements b.sub.0 to b.sub.p-1 arranged from a position P(i) to a position P(i+p-1) in a global format containing p+n binary elements arranged according to the positions P(1) to P(p+n), which global format is contained in one or more registers (K0-K7) as elementary formats is performed by a microprocessor (8) for carrying out instructions with respect to the elementary formats of clockwise rotation, counterclockwise rotation and an instruction of transfer of a binary element to a carry register (c), which instructions are stored in a read-only memory.

Abstract: A digital message M is transformed by means of an operation to modulo-N exponentiate M by a number e all these numbers being large-length integers, having n bits, which uses a sequence of two successive operations, the first in the form of:B.sub.i =a.sub.i.X+T.2.sup.mwhere B.sub.i and X are calculation variables, where a.sub.i is an extract of m bits of a second calculation variable A whose value results from a previous operation, which extract is taken in the decreasing order of weight of A, of rank i, and where T is a summing variable used for the calculation of the variable A, and the second operation consists of reducing the length of the variable B.sub.i. A modulo-N quasi-reduction is used because it is approximative (to the nearest small multiple of N), and may be applied systematically and without a sign test during a given number of successive operations which are chosen, after which a supplementary and systematic reduction is performed according to the same method.

Abstract: A device for testing an electric circuit or components of this circuit provided on a board (9), which board (9) is secured against a support (7) by an underpressure in a first chamber (15) during operation. An electrical connection is effected between the board (9) and an electronic test unit (69) of the device by means of a contact plate (81). The contact plate (81) is provided exchangeably on a partition wall (13) which hermetically seals off the first chamber (15) from a second chamber (17) and which can be moved in a direction transverse to the board (9) by a pressure difference between the two chambers (15, 17). The exchangeable contact plate (81) corresponds to the type of board (9) and activates a combination of test probes (49) from a set of test probes (49) provided in a matrix plate (45), which combination is unique for the type of board (9), after the partition wall (13) has been moved.

Abstract: In CCD arrangements, such as bidimensional image sensors, it is usual to provide the output register in the form of two (or more) horizontal registers. Via transverse connections between the horizontal registers, charge packets are transported from one horizontal register to the other horizontal register. In order to avoid delays during this transverse transport due to narrow channel effects, the clock electrodes of the first horizontal register adjoining the transverse connections are widened at the expense of adjacent clock electrodes. These widened electrodes may be in the trapezoidal form, as a result of which additional drift fields are induced below these electrodes.

Abstract: The invention relates to a magneto-optical recorder with magnetic-field modulation. It comprises a laser (8) for producing a light beam (6), an optical focussing system (9) for forming a focal spot (12), and a servo device (10) for maintaining the focal spot (12) in focus on the surface of a thermo-magnetic record carrier (4), and for supplying a correction signal (V.sub.c) which is representative of the position of the surface of said carrier. A current modulator modulates the current through a coil (15) of a magnetic head. A compensation device (7) is responsive to said correction signal (V.sub.c) to change a parameter influencing the field of the coil, in such a way that the field strength at the surface of said carrier (4) is substantially independant of the position of said surface.

Abstract: In a communication bus system all data is echoed by a common echo buffer station on a first bilevel unidirectional element or wire, in the form of sequential selfclocked bivalent information packets. Peripheral stations have clock extraction provisions for clocked interrogation of those packets, absorbing the information if required, and thereupon transmitting a self-determined non-selfclocked binary information value on a second bilevel unidirectional element or wire that has a wired-logic functionality (wired-OR, wired-AND) so that coexistently transmitting peripheral stations may be subjected to arbiter operation. A peripheral station may have clock extraction means and transfer the extracted clock on a third wire, in parallel with unclocked data on a fourth wire, third and fourth wire in parallel feeding a plurality of access modules. Any access module may then feed a fifth wire with its data, all fifth wires in parallel feeding the second wire via associated bridge elements.

Abstract: A method and device for the perspective display of a portion of topographic coordinate information of points on the surface of the earth proximate to the current position of a vehicle travelling thereon, utilizes a coordinate transformation to generate a perspective image from an apparent point of view above and behind the vehicle in a viewing direction, which, with the direction of travel of the vehicle, defines an imaginary plane which is perpendicular to the surface of the earth.

Abstract: Microcontroller comprising in particular a central processing unit (10), a set of memories (11, 12), a specialized processing module (13) for performing, in sequence, operations on v variable operands and k operands of parameter type (constant during the sequence), and an arrangement of internal buses (20, 21) for the exchange of addresses and data.

Abstract: A dielectric resonator is used in a magnetic resonance examination apparatus comprising a magnet system (31, 32) for generating a steady magnetic field in an examination space (2), a transmitter device (12, 13, 18, 28) for generating an RF field to be superposed on the steady magnetic field in an object (30) to be examined, a device for producing a resonance step-up of the RF field active in the object (30) to be examined, and a device for detecting magnetic resonance signals generated in the object (30) to be examined. Stronger B.sub.1 fields are created by at least one dielectric resonator (1, 5, 10, 16, 17, 20, 21) which neighbors the object (24) to be examined and which comprises a dielectric having a relative dielectric constant .epsilon..sub.

Abstract: For exact positioning of optical elements, a spectrometer is provided with a holder which is constructed using plates having a sector of circle shape and a side wall portion comprising a cylindrical surface portion. The cylindrical surface portion is provided with an exactly circular abutment face in which an entrance slot and an exit slot are provided. Relative to this abutment face, an entrance slit and an exit slit can be extremely exactly positioned with respect to one another along an exact circle. The holder is preferably constructed using two axially stacked compartments, in a cylindrical surface portion of which the slot or slots is/are provided between the compartments.

Abstract: A zero IF receiver which is capable of detecting short duration or CW signals and of operating over a large dynamic range includes an input terminal for receiving an input signal, a quadrature down-converter coupled to the input terminal for producing quadrature related, frequency down-converted signals in a pair of signal paths. These signal paths each include an amplifier having a substantially sinh.sup.-1 transfer characteristic so that the pair of signal paths produce substantially logarithmic quadrature related output signals which are coupled to a demodulator. The demodulator converts the quadrature related output signals into amplitude and frequency descriptions of the input signal relative to a center frequency of the receiver. The amplitude description is determined by selecting the one of the quadrature related output signals having the larger absolute value and applying an amplitude correction thereto.

Abstract: The invention relates to an epilating device having epilating rollers which are drivable in opposite directions, at the periphery have a wave-shaped cross-sectional profile, mesh together at their periphery by their cross-sectional profiles and are drivable by means of a motor, a single-phase synchronous motor without a non-reverse mechanism being provided for the purpose of driving an uneven number of epilating rollers.

Abstract: A programmable serial multiplier performing the multiplication of a multiplicand by a fixed constant coded on r bits is formed from a battery of (r/2)-1 addition cells (11.sub.O -11(r/2)-2) interconnected in series by a first input, a shift register formed from (r/2)+1 initializable flip-flops (10.sub.O -10.sub.r /2), and an interconnection channel. The latter makes it possible to program the serial multiplier in order to perform the multiplication by the fixed constant C, either with the aid of the value +C when the constant C contains, in binary notation, a number of 1s less than or equal to the number of 0s, or with the aid of the value -C in the reverse case. It may operate with a signed fixed constant C.A computational processor which carries out a linear transform of numerical data, implements such a multiplier. For each multiplication of the linear transform, the processor may operate either with the constant proper or with the constant's oppositely signed number.

Abstract: A self-aligning sampling system for sampling digital signals, for example in a logic analyzer includes an adjustable delay line fed by a system clock signal which delay line has tapping points for further clock signals. In conjunction with the system clock, the further clock signals are used to take several samples of the digital signal in a time slot of the system clock. In order to achieve equidistant sampling even in the case of a large process spread in elementary delay units of the delay line, the delay line is calibrated. The system clock is then connected to the data input and expressed in elementary delay units on the basis of measurement. Subsequently, the delay line between clock signal tapping points is adjusted on the basis thereof.

Abstract: Using a NAND and a NOR gate as input gates provides a simple and efficient input buffer. In the input buffer circuit, a chip select signal is applied in inverted form to the NOR gate and in non-invented form to the NAND gate. The resulting input buffer is both simpler and faster than earlier circuits.

Abstract: A monochromatic X-ray radiation source includes an anode for producing X-ray radiation, a target enclosed by the anode for converting X-ray radiation into fluorescence radiation and a screen located between the target and the anode for screen the target from electrons. A higher output of fluorescence radiation is attained in that the screen comprises an element having an atomic number greater than 50, for example, tungsten or tantalum.

Abstract: The described optical transmitter comprises a laser diode (2) and optically coupled thereto a photodiode (3) operating as a monitor diode. The photoelectric current of the monitor diode (3) is used for adjusting the light power of the laser diode (2). In addition, the optical transmitter includes modulators used for modulating the current of the laser diode (IL) by a useful signal (b.sub.n) and a pilot signal (B.sub.k). The device includes circuitry to control the laser diode, in response to the photodiode, so that jitter in the signal is avoided. The device is capable of operation with bit frequencies in the GHz range.

Abstract: Magnetic head including a core (1, 3) of soft magnetic material having a contact face (7) and a winding aperture (5) and a coil (14) wound around the core. A layer (13) of a superconducting material is present in the non-magnetic transducing gap (11) in the core and a layer (15) of a superconducting material is provided on at least a plurality of the outer faces, for example the side faces (17).