Abstract: A local clock signal generation system is disclosed including multiple local clock buffers each receiving a global clock signal and producing a version of one or more local clock signals derived from the global clock signal. Each local clock buffer includes an input section and an output section. The input sections are substantially identical such that timing differences between the versions of the one or more local clock signals are reduced. An electronic circuit is described including the local clock signal generation system and a latch (e.g., a master latch of a flip-flop). A local clock buffer produces a gating signal and a local clock signal received by the latch. When the gating signal is a certain logic value, the local clock signal is a steady logic value, and the latch produces an input data signal as an output signal. An integrated circuit including the electronic circuit is disclosed.

Abstract: A level shift circuit that reduces PMOS to NMOS device contention while decreasing output rise delays. The invention includes a device, comprising: a level shift circuit for shifting a signal at a first voltage at an input node to a second voltage at an output node; a boost circuit, driven by the second voltage, for decreasing a transition time of the signal between the first and second voltage; and a trigger circuit, coupled to an input of the boost circuit, for turning off the boost circuit when the signal at the output node reaches a predetermined voltage level.

Abstract: A switched capacitor circuit for use in a voltage controlled oscillator (VCO) capable of minimizing clock feedthrough effect and an undesired momentary frequency drift in the VCO output frequency when the switched capacitor circuit is shut off. By gradually switching the switched capacitor circuit from an on state to an off state the clock feedthrough effect can be minimized. Several differently sized switch elements are used to selectively switch the capacitor from an internal capacitive node to ground. When switching the switched capacitor circuit to an off state, the control signals are sequenced to shut the switch elements off in order based on decreasing switch size. The smallest switch element can have a low-pass filter added to its control terminal to further decrease the clock feedthrough effect.

Abstract: A switched capacitor circuit for use in a voltage controlled oscillator (VCO) capable of minimizing clock feedthrough effect and an undesired momentary frequency drift in the VCO output frequency when the switched capacitor circuit is shut off. By gradually switching the switched capacitor circuit from an on state to an off state the clock feedthrough effect can be minimized. Several differently sized switch elements are used to selectively switch the capacitor from an internal capacitive node to ground. When switching the switched capacitor circuit to an off state, the control signals are sequenced to shut the switch elements off in order based on decreasing switch size. The smallest switch element can have a low-pass filter added to its control terminal to further decrease the clock feedthrough effect.

Abstract: A feedback control system and method thereof are provided. The feedback control method includes (a) comparing the level of a reference signal with the levels of first and second signals, (b) if the levels of the first and second signals are lower than the level of the reference signal, generating a first control signal, if the levels of the first and second signals are higher than the level of the reference signal, generating a second control signal, and if the level of the reference signal is between the level of the first signal and the level of the second signal, generating a third control signal, (c) controlling the level of an output signal in response to the first through third control signals, and (d) outputting the controlled output signal and generating the first signal and the second signal.

Abstract: The present invention provides a balance apparatus for line input capacitors. A programmable N-current-sink is connected in parallel to a high-side capacitor, and a programmable P-current-sink is connected in parallel to a low-side capacitor. A resistor network is coupled between the high-side capacitor and the low-side capacitor to generate a differential voltage. The differential voltage is the voltage difference of the high side capacitor and the low side capacitor. When the voltage of the high-side capacitor is higher than the voltage of the low-side capacitor, the programmable N-current-sink will sink an N-current that is proportional to the differential voltage. If the voltage of the low-side capacitor is higher than the voltage of the high-side capacitor, the programmable P-current-sink will sink a P-current that is also proportional to the differential voltage. When the differential voltage is small, both the N-current-sink and the P-current-sink will be turned off to reduce power consumption.

Abstract: Connected to a power element having a first electrode, a second electrode, and a control electrode, a power element protection circuit detects a voltage between the first and second electrodes of the power element and the current flowing through the power element, then logarithmically converts a current proportional to the detected voltage and a current proportional to the detected current individually, then adds the results together, then subtracts a predetermined value from the sum, then antilogarithmically converts the result with an antilogarithmic converter, and then limits the driving of the power element based on the output of the antilogarithmic converter.

Abstract: An inrush current at beginning of operation of a charge pump circuit is reduced to prevent adverse effect on other circuits in a system. Charge transfer MOS transistors are connected in series. One end of each coupling capacitor is connected to each connecting point of the charge transfer MOS transistors. An output from each clock driver is applied on the other end of the respective coupling capacitor. Each clock driver includes a first clock driver and a second clock driver having higher driving capacity than the first clock driver. Each clock driver is controlled so that the first clock driver is put into operation at first and at the end of a predetermined elapsed time it is stopped and the second clock driver is put into operation.

Abstract: Integrated circuits are provided that include a voltage control circuit that is configured to adjust a circuit voltage that is outside a predetermined circuit voltage specification to within the predetermined circuit voltage specification so that the integrated circuit device is no longer defective. Integrated circuits are also provided that include a signal time delay control circuit that is configured to adjust a circuit delay time that is outside a predetermined circuit delay time specification to within the predetermined circuit delay time specification so that the integrated circuit device is no longer defective. Corresponding methods of operation are also provided.

Abstract: Disclosed is a variable output-type constant current source circuit capable of varying its output current in a stepwise manner without the complication in circuit configuration and the increase in size of a semiconductor circuit board for incorporating the circuit therein. The constant current source circuit comprises a first self-biasing type constant current circuit 3a configured such that transistors M1, M2 are operable to cooperatively supply a given voltage across a resistor RS to generate a stabilized current IR1. In order to vary the output current, the constant current source circuit includes a switching circuit 5 (transistor M5) connected in series to a series circuit connecting in series the transistor M1 and the resistor RS, and a second constant current circuit 4 connected in parallel to a series circuit connecting in series the transistor M1, the resistor RS and the transistor M5.

Abstract: There is a need for an inexpensive, high-performance, fully-integrable, multi-standard transceiver. The invention provides a topology that satisfies this need, consisting of: an active mixer, followed by a high pass filter, and a passive mixer. The input signal is modulated up, or demodulated down, using a pair of complementary, aperiodic mixing signals. The use of aperiodic mixing signals allows a fully-integrated transceiver to be built. Several embodiments of the active mixer are also presented, including those having electrically-adjustable performance and allowing multiple RF signal inputs. This allows the topology of the invention to be employed in multi-band, multi-frequency applications, while still providing high performance.

Abstract: The invention provides robust and non-invasive calibration of an adaptive signal conditioning system having a signal conditioning block in the signal path to a signal conversion system, and a feedback path with a number of feedback components for enabling adaptation, by means of a parameter adaptation block, of the parameters used in the signal conditioning. In order to calibrate the feedback path, a well-defined reference signal is inserted into the feedback path, and an appropriate calibration coefficient is then determined by a coefficient calibrator in response to the received reference signal. The calibration coefficient is provided to a compensator, which effectively compensates for changes in the transfer characteristics of the feedback path due to factors such as variations in ambient temperature and component aging.

Abstract: An operational amplifier circuit is constituted by first and second inverted amplifier circuits (A1, A2) that receive first and second input signals, a third inverted amplifier circuit (A3) that receives an estimated common-mode output signal and an output signal from the first inverted amplifier circuit and outputs first and second output signals, a fourth inverted amplifier circuit (A4) that receives the estimated common-mode output signal and an output signal from the second inverted amplifier circuit and outputs third and fourth output signals, where the estimated common-mode output signal is generated by adding the second output signal and the fourth output signal, and first and second non-inverted amplifier circuits (A5, A6) that receive the estimated common-mode output signal and feed it back to the first and second inverted amplifier circuits.

Abstract: A power supply voltage required on the basis of information of setting transmission power to be output is supplied, thereby minimizing power consumption. A transmission circuit comprises a driver amplifier 3 whose gain is controlled by a first control voltage Vc1 for setting transmission power and a power amplifier 4 connected to the post-stage of the power amplifier 3. A power supply circuit 5 to which the first control voltage Vc1 is input and whose output voltage is controlled by the first control voltage Vc1 is provided. A voltage required for the power amplifier 4 when outputting the transmission power set by the first control voltage Vc1 is supplied from the power supply circuit 5.

Abstract: A multi-band low noise amplifier comprising: a plurality of matching networks, a plurality of differential pairs, a pair of common base transistors, a pair of inductors, a pair of variable capacitors, a pair of inductors and a current generator. Bases of said plurality of differential pairs are coupled to outputs of said plurality of input matching networks. Emitters and collectors of said plurality of differential pairs are connected. Emitters of said common base transistor pairs are coupled to collectors of said plurality of differential pairs. The inductors are coupled to collectors of said common base transistor and a power supply. The capacitors and the inductors form a resonator pair. The inductors are coupled to emitters of said plurality of differential pairs. The inductor pairs are interlinked. The current generators are coupled to a coupling point of said inductors and to ground.

Abstract: An electronic amplifier circuit comprising an operational amplifier circuit, such as a two-stage operational amplifier circuit, in tandem with a operational transconductance amplifier. The electronic amplifier circuit has high open-loop gain and high gain-bandwidth while maintaining stability over a wide range of operating parameters.

Abstract: Disclosed are systems and methods which provide very linear amplification of signals using a linearized transconductance circuit. A transconductance amplifier configuration is shown which provides highly linearized operation utilizing a Darlington pair feedback circuit. Also shown are gain control configurations in which current steering circuitry is adapted to operate in its most linear region.

Abstract: A method for extending the linear range of operation of an amplifier includes monitoring a transistor voltage of a transistor of an amplifier. The transistor is coupled to a variable current source applying a bias current to the transistor. The method continues by monitoring an output voltage of the amplifier and by determining whether the transistor voltage is within a predetermined range of the output voltage. If the transistor voltage is not within a predetermined range of the output voltage, the method continues by decreasing the bias current applied to the transistor. If the transistor voltage is within a predetermined range of the output voltage and if the bias current has not previously been decreased, the method continues by increasing the bias current applied to the transistor.

Abstract: A multicell amplifier comprises a first divider unit, which receives the input signal of the amplifier, divides it into 2N subsignals, amplifies them and recombines the amplified signals in two N-way combiners to form two local output signals; two further divider units which take the local output signals and divide them into 4N subsignals, amplify them and recombine the amplified signals to form three local output signals; and two combiner units which take the three local output signals and divide them into 4N subsignals, amplify them and recombine the amplified signals to provide the output signal of the amplifier.

Abstract: A multi-stage, variable gain amplifier whose linearity is relatively insensitive to variations in gain control is disclosed. The amplifier includes a primary cascoded pair of transistors for producing a primary output current from an input voltage as a function of a primary cascode control voltage. The amplifier further includes one or more secondary cascoded pairs of transistors coupled to the primary cascoded pair of transistors for producing one or more secondary output currents from the input voltage as a function of one or more secondary cascode control voltages.

Abstract: According to some embodiments, a low gain phase-locked loop circuit is provided.

Abstract: Method and related apparatus for realizing frequency-multiplication by generating a high frequency signal according to a plurality of low frequency signals. The method includes: according to a plurality output signals generated by a phase-locked loop (PLL) or a delay-locked loop (DLL), generating a plurality of reference signals with a same frequency and different phases; when a number of the reference signals with signal level high is greater than a number of the reference signals with signal level low, making a signal level of the output signal remains a first level; otherwise, making the signal level of the output signal remains a second level substantially different from the first level. Thus the frequency of the output signals is a multiplication of the frequency of the input signals.

Abstract: A downhole crystal-based clock that is substantially insensitive to the factors that cause frequency deviation. The clock may be maintained at a predetermined temperature using a temperature sensing device and a heating device, where the predetermined temperature corresponds to the temperature at which the crystal experiences only slight frequency deviation as a function of temperature. A microprocessor may monitor the clock and compensate for long-term aging effects of the crystal according to a predetermined algorithm. The predetermined algorithm may represent long-term aging effects of the crystal which were derived by comparing the crystal clock to a more accurate clock (e.g., an atomic clock) prior to placing the clock downhole. In this manner, the crystal-based clock may be substantially free from the factors that cause frequency, and therefore time variations.

Abstract: In a modulation system,.in order to provide a two-level signal with a desired modulation which is suited to be amplified by a switching mode power amplifier, the modulation system may include a first constant envelope modulator modulating a signal according to a first control signal, a second constant envelope modulator modulating a signal according to a second control signal, and a combining portion combining the output signal of the first and said second constant envelope modulator to a single, two-level pulse-width-modulated signal. The information which is to be represented by the modulation of the single, two-level pulse-width-modulated signal is coded in the first and the second control signals. The invention relates equally to a corresponding method for generating a modulated signal.

Abstract: The present invention provides an electro-magnetic interference protection circuit for a clock buffer. The present invention not only uses a ferrite bead that is serially connected with the power source of the clock buffer to protect the clock buffer from electro-magnetic interference. The ferrite bead also connects in parallel with a capacitor to reduce the distortion of a clock signal out-putting by the clock buffer due to the ferrite bead, thereby making the communication devices work properly.

Abstract: A waveguide unit including a vertically polarized waveguide, a horizontally polarized waveguide, and a waveguide type-polarized wave converter interposed between said waveguides. The waveguide type-polarized wave converter has a slit, the shape of which being combination of two quadrate parts and a connecting part for connecting the two quadrate parts. Those polarized waveguides and polarized wave converter are integrally manufactured but can be divided into two parts.

Abstract: A nonreciprocal circuit element includes a yoke body; a magnetic substrate; a plurality of line conductors; a plurality of capacitance elements; and a magnet member. The plurality of line conductors overlap each other on the main surface of the magnetic substrate in such a manner as to be insulated from each other and are connected to each other on the other surface of the magnetic substrate. The end portions of the line conductors which are made to overlap on the main surface of the magnetic substrate are connected correspondingly to the capacitance elements, a termination resistor is connected to one of the line conductors, and the width of the line conductor to which the termination resistor is connected is smaller than the individual widths of a plurality of the other line conductors.

Abstract: A multilayer circuit board for high-frequency signals includes: a multilayer wiring board unit including, at least one wiring layer, one or more ground layers configured by a conductive material, insulating layers between the layers, and a first external electrode electrically connected to a transmission line on an episurface; and a connector unit including a second external electrode electrically connected to the first external electrode, and a fitting portion for holding on the multilayer wiring board unit an external circuit board or an external connector. The distance d between the first external electrode (7) and the ground layer perpendicularly below and most closely disposed to the first external electrode is determined within the range dl≦d≦du with respect to the values dl and du defined based on tolerance of the impedance &Dgr;Z.

Abstract: Three dimensional electronic and optical coupling devices that are capable of providing high speed coupling over a large frequency range while limiting the amount of space consumption in the communications network. An optical or electrical coupling device comprises a first substrate and a second substrate adjacent to the first substrate having one or more optical waveguides or microstrips formed thereon. The substrates will have disposed thereon conductive microstrips and/or dielectric elements. The one or more optical waveguides or microstrips formed on the first substrate correspond to at least one optical waveguides or microstrips formed on the second substrate so as to facilitate optical coupling between the corresponding waveguides. Precise spacing between the substrates and precise spacing between the optical waveguides or microstrips facilitate the requisite optical/RF coupling.

Abstract: A transmission line balun eliminates unwanted reflection of signal energy coupling to a ground plane. A junction of the conductive segments connected to the unbalanced port on the balun is connected to the ground plane with a resistor. The selected junction is a virtual ground of the balun, so the presence of the resistor does not degrade the balun performance. The resistor dissipates the energy from the parasitic mode propagating with the ground plane so that no signal is reflected back to short out the signal source. The value of the resistor is selected to facilitate maximum termination of the parasitic mode propagation.

Abstract: A balanced line switching apparatus that provides high isolation at an expense of a marginal increase of loss. Practical implementation can give as much as 40 dB isolation in a single stage.

Abstract: A phase control mechanism for broadcast RF transmission using pairs of transmission lines feeding a dual port antenna continuously monitors phase error between either the signals carried by the two lines or the physical heights of the bottom elbows where the two lines turn upward to ascend a tower. The mechanism minimizes phase error by altering the propagation time in one or both lines. Causes for such phase errors include climatic conditions such as unmatched heating by sunlight and cooling by wind. Effects of such phase errors include beam tilt and reduction in effective broadcasting range. Systems for which such phase control is applicable include broadband transmission systems carrying one or more channels of television and radiating them using a single antenna on a tower.

Abstract: An object of the present invention is to obtain a waveguide type polarizer, which enables miniaturization thereof, shortening of an axis, and broad band promotion, and which has high performance. In order to attain the object, the waveguide type polarizer includes: a first rectangular main waveguide 1; first to fourth rectangular branching waveguides 2a to 2d branching perpendicularly to the first rectangular main waveguide 1; a short-circuit plate 3 connected to one terminal of the first rectangular main waveguide 1; a metallic block 4 provided on the short-circuit plate 3; a rectangular waveguide step 5 connected to the other terminal of the first rectangular main waveguide 1; and a second rectangular main waveguide 6 connected to the rectangular waveguide step 5.

Abstract: The invention relates to an arrangement and method for combining electric signals. The arrangement comprises: an antenna element (270) for receiving first electric signals from the environment; a receiver cable (210) in connection with the antenna element (270) for carrying the first electric signals; at least one antenna feeder cable (212) for carrying second electric signals; a transmitting antenna (250) in connection with said at least one antenna feeder cable (212) for transmitting the second electric signals, and at least one cable coupler (120) in said receiver cable (210), in which the polarity of said at least one cable coupler (120) is reversed in order to induce a local leakage current. Said at least one cable coupler (120) is arranged next to said at least one antenna feeder cable (212) for coupling the first electric signals and the second electric signals to the receiver cable (210).

Abstract: An improved radio-frequency filter is distinguished by the following features:

Abstract: A resonator device including a plurality of resonance units formed on a dielectric substrate, each resonance unit having a plurality of conductor lines forming a capacitive area and an inductive area in a ring shape.

Abstract: In the present invention a multi-bit time-delay adjuster using Radio Frequency (RF) MicroElectroMechanical (MEM) switches is disclosed for applications in MCPAs with feed-forward linearization technique. The MEM switching system used in the multi-bit time-delay adjuster makes it possible to automatic control the time-delay match with very high precision required in feed-forward MultiCarrier Power Amplifiers (MCPA), instead of a manual trimming process. A searching process suitable for the automatic control of time-delay match is also introduced and demonstrated by an example of a four-bit time-delay adjuster.

Abstract: The invention provides a filter network comprising a plurality of circuit branches, each circuit branch comprising one or more filter elements. At least one of the circuit branches comprises a resonant circuit and is preferably arranged between the circuit path and ground. The filter network further comprises a switch device associated with the resonant circuit, the switch device being operable between an on state, in which the resonant circuit is connected to said circuit path, and an off state in which the resonant circuit is substantially isolated from said circuit path. The filter network also includes a switch control input for receiving a signal for operating the switch device between the on and off states. Switching in and out the resonant circuit changes the operational characteristics of the filter.

Abstract: An apparatus such as a thin film resonator has a bottom electrode, a top electrode, and a composite layer between the two electrodes. The composite layer includes a piezoelectric (PZ) layer having a first coupling coefficient and a coupling coefficient control (CCC) layer having a second coupling coefficient. By varying the relative thicknesses of the PZ layer and the CCC layer during the manufacturing process, the coupling coefficient of the resonator can be established (to any value between the first coupling coefficient and the second coupling coefficient) with minimal impact on resonant frequency. Further, it is relatively less difficult to fabricate the PZ layer and the CCC layer having the desired coupling coefficient (as a combination of the first coupling coefficient and the second coupling coefficient) compared to the difficulties of fabrication of a uniform PZ layer having the desired coupling coefficient.

Abstract: A surface acoustic wave arrangement has at least two interdigital transducers being provided on a piezoelectric substrate along an acoustic path, with at least one of the interdigital transducers being a fan transducer which is divided in a transverse direction into edge tracks and a center track. The acoustic wave excited in the edge tracks can be radiated either bidirectionally or unidirectionally in a predominant direction. On the other hand, the center track is formed so that the unidirectional radiation of the wave takes place in a direction opposite the predominant direction. In this manner, the signal transmission is suppressed in the frequency range corresponding to the finger period in the center track within the passband range of the transfer function. The obtained notch in the transfer function is used, for example, in receivers of terrestrial and satellite-based signals for suppressing the terrestrial signals in the satellite path of the receiver.

Abstract: Filter circuitry is provided with a series element and a parallel element. The filter circuitry transmits signals that fall within a certain passband and attenuates signals that don't fall within the certain passband. The series element is comprised of a resonance element having antiresonance characteristics, and the parallel element is comprised of a series circuit including an inductor and a capacitor.

Abstract: The invention relates to a quadruple mode microwave filter having coupled cavities with a plurality of transmission zeros, said filter comprising at least one rectangular parallelepiped-shaped quadruple mode cavity, at least two rectangular irises, and two input/output waveguides. Tuning and coupling of the filter are obtained exclusively by the dimensions and mutual disposition of the at least one resonant cavity and the irises, without any screw or other tuning mechanism. All the faces of the cavities and the irises are either parallel or perpendicular to each other. In a preferred embodiment the irises are offcentered along the two transverse axes. According to one advantageous feature, the input mode and the output mode are the same, preferably the TE 10 fundamental mode.

Abstract: An electromagnetic wave is input to a resonator 14 filled with a dielectric and a gas, and a resonance frequency, an insertion loss and a half-power width in the resonance mode of the electromagnetic wave output from the resonator 14 are measured by a network analyzer 16 in response to the input of the electromagnetic wave and the complex dielectric constant of the dielectric is calculated from the resonance frequency, the insertion loss and the half-power width which are thus measured.

Abstract: The invention provides an electromagnetic relay excellent in insulating property and high in opening and closing characteristics and productivity.

Abstract: A deflecting yoke apparatus comprising first and second frame coils configured to correct a vertical horizontal misconvergence first and second main coils and first and second sub-coils which are wound around a core and configured to deflect in a vertical direction electron beams which have passed through a magnetic field generated by the first and second frame coils, a first deflecting current supply portion configured to pass a serriform deflecting current to the first and second main coils, and a second deflecting current supply portion configured to supply to the first and second sub-coils through a first and second diodes connected in parallel so as to have opposed directions a deflecting current which is supplied to the first and second main coils by the first deflecting current supply portion.

Abstract: Magnetic actuator having a closed magnetic circuit (26) capable of guiding a magnetic flux. The magnetic circuit (26) comprises a fixed magnetic part (30, 31, 32) with a yoke (30) and a mobile part (22), magnetically connected to each other and also at least one main air gap (29) delimited by at least one portion (28) of the mobile part (22) and by the yoke (30). In the main air gap (29), the flux is closed by being set up approximately transverse to the mobile part (22). The fixed part (30, 31, 32) also comprises flux recuperation means (40) that contribute with the mobile part (22) to delimiting an auxiliary air gap (38) in which the magnetic flux is set up laterally to the mobile part (22). The flux is contained on each side of the main air gap (29), on one side by the yoke (30), and on the other side jointly by the mobile part (22) and the flux recuperation means (40) through the part (28) contributing to delimiting the main air gap (29).

Abstract: A magnetic field generator comprises a pair of pole-piece units. The pair of pole-piece units respectively include plate yokes. Each of the plate yokes includes a surface facing the other's and provided with a permanent magnet group and a pole piece. The pole piece includes an annular projection having a plurality of annular-projection pieces and a permanent magnet for reduction of magnetic flux leakage installed on an outside surface of each annular-projection piece. When assembling the pole piece, first, the permanent magnet for reduction of magnetic flux leakage is fixed on the outside surface of each annular-projection piece. At this time, the permanent magnet is slid on the flat outside surface of the annular-projection piece, to a desired position on the annular-projection piece, and then fixed. Each of the annular-projection pieces mounted with the permanent magnet is fixed on a base plate.

Abstract: A magnetic element for multi-phase is composed by burying a plurality of coils in a composite magnetic material such that a negative coupling of magnetic fluxes or a positive coupling of magnetic fluxes exists between at least two coils. This structure more miniaturizes inductors, or choke coils as the multi-phase magnetic element suitably used for application of a large current to many kinds of electronic equipment. Such multi-phase magnetic element has an excellent ripple current property.

Abstract: The invention is a device and method for eliminating core excitation losses in a distribution transformer when the transformer is not supplying power to loads. The invention consists of sensors, a control circuit, a user interface and a power contactor. The power contactor is connected on the line side of a transformer and is opened or closed automatically based on preprogrammed time or load criteria determined by the control circuit. In one operational mode and when the transformer is disconnected from the line, the control board generates low power pulses at the transformer load connection points in order to “search” for loads. If a load is detected, the transformer is reconnected by way of contactor closure. If the transformer load drops to zero, for a predetermined amount of time, the transformer is again disconnected and the pulsed load search is reestablished.

Abstract: The invention relates to a bushing-type transformer (1) comprising a conductive element (5) forming the primary conductor, supporting a flat contact surface (7) on one end thereof and a plug-in contact element (8) on the other end thereof, whereby the plug-in contact element (8) is embodied in a rotationally symmetrical manner and the rotational axis is arranged parallel to the flat contact surface (7). Said transformer also comprises a secondary winding (6) which surrounds the conductive piece (5) in an annular manner. The conductive element (5) extends in a linear manner and the plug-in contact element (8) is arranged on the surface area of the conductive piece (5).