Abstract: A millimeter waveband switch which enables high isolation without increasing passing loss, includes a first switching element that is connected in series between input and output terminals through which a signal passes; and a first transmission line having an electrical length of ½ wavelength and which is connected in parallel with the first switching element. Alternatively, the millimeter waveband switch may include: a first switching element having a first end connected in parallel to input and output terminals through which a signal passes; a first transmission line having an electrical length of ½ wavelength which is connected in parallel with the first switching element; and a second transmission line having an electrical length of ¼ wavelength and which is connected between aground and a second end of her first switching element.

Abstract: There has been a problem that the distortion characteristic of a switch circuit for a high frequency is deteriorated. A switch circuit in accordance with one aspect of the present invention includes a transistor connected in series between input and output terminals, a control terminal that receives a signal to control the conductive state of the transistor, a first resistor connected between the control electrode of the transistor and the control terminal, and a series circuit of a diode and a second resistor, the series circuit being connected in parallel with the first resistor between the control terminal and the control electrode of the transistor.

Abstract: Provided is a switching circuit for a millimeter waveband control circuit. The switching circuit for a millimeter waveband control circuit includes a switching cell disposed on a signal port path to match an interested frequency and including at least one transistor coupled vertically to an input/output transmission line and a plurality of ground via holes disposed symmetrically in an upper portion and a lower portion of the input/output transmission line; capacitors for stabilizing a bias of the switching cell; and bias pads coupled in parallel to the capacitor to control the switching cell.

Abstract: A switch element includes a switch device having a drain, a source and a plurality of gates, and at least one additional interconnect located between the plurality of gates, the additional interconnect operative to establish a constant potential between the at least two gates.

Abstract: A single-die multi-band switch includes a plurality of transmitter ports and a plurality of receiver ports, any one of which is selected to be connected to an antenna port. At least some of these switching topologies use a branched or cascaded switching system in order to reduce signal insertion loss. It is preferred that the individual switching elements be field effect transistors. The switching topologies employed include series-connected groups of transistors and interdigitated FETs.

Abstract: An RF switch includes first, second and third transmission lines for forming ports, respectively, and first, second and third slot line pattern portions connected to one another, for transferring signals to the first, second and third transmission lines, respectively. The first slot line pattern portion has a slot line pattern for transferring a signal received from the first transmission line to a connection point with the other slot line pattern portions, and a switching circuit for shorting the gap of a corresponding slot line and thus blocking the signal transfer. The second slot line pattern portion includes a loop slot line formed by a first and a second half loop slot line, a second sub-slot line for transferring a signal received from the connection point to the second transmission line through the loop slot line, and a switching circuit for shorting the gap of a corresponding slot line.

Abstract: A low-loss Radio Frequency (RF) switch for high-power RF signals. The RF switch includes a first-biasing circuit connected to a first transistor and a second-biasing circuit connected to a second transistor. The RF switch switches its output signal between a first input signal and a second input signal. The first transistor is in a conduction state and the second transistor is in a non-conduction state when the first input signal is to be conducted to the output signal. The first-biasing circuit biases the first transistor at a first voltage for increasing conduction of the first input signal and the second-biasing circuit biases the second transistor at a second voltage for decreasing conduction of the first input signal. Moreover, the second transistor is in a conduction state and the first transistor is in a non-conduction state when the second input signal is to be conducted to the output signal.

Abstract: Disclosed is a switch circuit capable of reducing distortion caused by harmonics and preventing an increase in insertion loss even if the number of ports increases. The switching circuit includes one common output port, M first switches having one set of ends connected in common to a first node (M?2 where M is a constant), N second switches having one set of ends connected in common to the common output port (N?1 where N is a constant), a third switch having one end connected to the common output port and the other end connected to the first node, M first input ports respectively connected to the other set of ends of the first switches, and N second input ports respectively connected to the other set of ends of the second switches. One selected among the first input ports and the second input ports is connected to the common output port, and if one of the first input ports is selected, the third switch is closed.

Abstract: The invention provides a phase shifter with flexible control voltage that is useful with all RF systems that phase shift a RF signal. The phase shifter according to the present invention may comprise transistors used as switching elements. In one aspect, the phase shifter provides the option of controlling a phase shifter with either a positive or a negative voltage control signal. For example, the dc ground of the transistors included in the phase shifter may be floated, either fixed or adjusted. The RF grounding of the transistors may be achieved by in-band resonant capacitors. Thus, the control voltage provided to the transistors is flexible in that it may be connected to a positive or negative control voltage, or it may be connected to ground, or it may swing from a positive control voltage to a negative control voltage or vice versa.

Abstract: Embodiments of the invention may provide for a CMOS antenna switch, which may be referred to as a CMOS SPDT switch. The CMOS antenna switch may operate at a plurality of frequencies, perhaps around 900 MHz 1.9 GHz and 2.1 GHz according to an embodiment of the invention. The CMOS antenna switch may include both a receiver switch and a transmit switch. The receiver switch may utilize a multi-stack transistor with body substrate switching and source and body connection along with body floating technique to block high power signals from the transmit path by preventing channel formation of the device in OFF state as well as to maintain low insertion loss at the receiver path. Example embodiments of the CMOS antenna switch may provide for 35 dBm P 1 dB at both bands (e.g., 900 MHz and 1.9 GHz and 2.1 GHz). In addition, a ?60 dBc second and third harmonic up to 28 dBm input power to the switch, may be obtained according to example embodiments of the invention.

Abstract: The invention provides a phase shifter with flexible control voltage that is useful with all RF systems that phase shift a RF signal. The phase shifter according to the present invention may comprise transistors used as switching elements. In one aspect, the phase shifter provides the option of controlling a phase shifter with either a positive or a negative voltage control signal. For example, the dc ground of the transistors included in the phase shifter may be floated, either fixed or adjusted. The RF grounding of the transistors may be achieved by in-band resonant capacitors. Thus, the control voltage provided to the transistors is flexible in that it may be connected to a positive or negative control voltage, or it may be connected to ground, or it may swing from a positive control voltage to a negative control voltage or vice versa.

Abstract: According to one exemplary embodiment, a switching module includes a first harmonic phase tuning filter coupled to a first input of an RF switch. The first harmonic phase tuning filter is configured to provide an output impedance that substantially matches an input impedance of the RF switch at approximately a fundamental frequency and to provide a high impedance at approximately a harmonic frequency generated by the RF switch. The first harmonic phase tuning filter includes an LC circuit coupled between input and output terminals of the first harmonic phase tuning filter and tuned to provide the high impedance at approximately the harmonic frequency generated by the RF switch. The RF switching module further includes a second harmonic phase tuning filter coupled to a second input of the RF switch. The first and second harmonic phase tuning filters can be fabricated on a single semiconductor die.

Abstract: The present invention provides a PIN diode switch circuit capable of sufficiently suppressing the generation of burst noise with each switching operation. The PIN diode switch circuit is switched to a state in which a terminal (X) and a terminal (Z) are connected to each other and a state in which a terminal (Y) and the terminal (Z) are connected to each other, by forward bias and reverse bias of PIN diodes (3 and 4). In the PIN diode switch circuit, a time constant circuit (51) and a snubber circuit (54) are provided in a path of a control signal, which extends from a terminal (CX) to the PIN diode (3), and a time constant circuit (61) and a snubber circuit (64) are provided in a path of a control signal, which extends from a to/urinal (CY) to the PIN diode (4), thereby suppressing burst noise that appears at a connecting point (Q) of a capacitor (5) and a coil (6).

Abstract: A non-reflective ring topology MPNT switching device comprises at least two poles, at least four throws, plural main switches, and plural bridge switches. The bridge switches enable all throws to be non-reflective throughout a wide frequency range. Each main switch is connected between one of the poles and one of the throws. Each bridge switch is connected between two of the throws, and each throw is connected to at least M+1 of the bridge switches, M being the pole count. In operation, each of M of the main switches has a first (ON) state and is connected to one of M active throws. For each active throw, each bridge switch connected to the active throw has a second (OFF) state. For each non-active throw, one bridge switch connected to the non-active throw has the first (ON) state and each other connected bridge switch has the second (OFF) state.

Abstract: Disclosed is a microwave phase shifter including switches each of which utilizes resonance between an off-capacitance of an FET and an inductor connected in parallel with the off-capacitance of the FET, an LPF, and an HPF, a series circuit of an inductor and an MIM capacitor is arranged in parallel with the FET in each portion of the resonance. In a layout of the LC series-connected circuit, though the inductor is of a non-close-packed structure, a metal member or a dielectric material having a relative dielectric constant higher than that of a dielectric substrate is arranged in a free space in a central portion of the inductor.

Abstract: The invention relates to a compact power-agile filter. The filter is a capacitance-weight filter comprising two electromagnetically-coupled oscillating circuits. Each oscillating circuit comprises capacitance weights. Each capacitance weight is controlled by signals. The filter comprises at least one motherboard and one daughterboard which are physically separate. The daughterboard comprises the capacitance weights, the motherboard comprises all the oscillating circuits. In particular, the invention applies to the power filter included in a radiocommunication system amplification module. For example, the invention can be used by a radiocommunication system that can be programmed by software means adapting to a range of signals extending over a wide frequency band.

Abstract: A high-frequency switching circuit module includes a high-frequency switch that includes an FET switching element and that selectively connects between a common input/output terminal and one of input/output terminals, and a matching circuit that is provided to the common input/output terminal Pc and is not provided to the input/output terminals. Although a non-selected input/output terminal of the high-frequency switch acts as a capacitor and the impedance between the common input/output terminal and a selected input/output terminal is displaced from a normal impedance, the displacement is corrected by the matching circuit connected to the common input/output terminal such that the impedance viewed from the common input/output terminal Pc to the high-frequency switch is made equal to the normal impedance. Accordingly, a high-frequency switching circuit module having a small overall size and achieving impedance matching for each terminal is provided.

Abstract: According to one exemplary embodiment, a switching module includes a first harmonic phase tuning filter coupled to a first input of an RF switch. The first harmonic phase tuning filter is configured to provide an output impedance that substantially matches an input impedance of the RF switch at approximately a fundamental frequency and to provide a low impedance at approximately a harmonic frequency generated by the RF switch. The first harmonic phase tuning filter includes an LC circuit coupled between an output terminal of the first harmonic phase tuning filter and a ground and tuned to provide the low impedance at approximately the harmonic frequency generated by the RF switch. The RF switching module further includes a second harmonic phase tuning filter coupled to a second input of the RF switch. The first and second harmonic phase tuning filters can be fabricated on a single semiconductor die.

Abstract: In an integrated circuit a microwave signal is routed through a selected signal path. Routing is accomplished by switching to determine the signal path. Control signals are applied remotely. The microwave integrated circuit is programmable by virtue of the ability to command selection of a signal path. The signal path is chosen to include or avoid selected “RF functional elements,” i.e., components through which radio frequency signals may be routed. RF functional elements may include, for example, amplifiers, mixers, attenuators, and phase shifters. Aspects of programmability in the integrated circuit include the provision of the functional circuit elements for selectable connection in signal paths, the switching and interconnect technologies used to switch and connect between them, and the arrangement of the functional circuit elements in relationship to each other.

Abstract: A high-frequency switch is constructed by connecting a first diode and a second diode that function as switching elements, inductors, capacitors, and resistors. One end of the resistor is connected between the first diode and the second diode, and the other end of the resistor is connected to the ground. Thus, charges accumulated in the diodes in the ON states are immediately released to ground via the resistor. Accordingly, quick switching from the transmission mode to the reception mode by switching of a control power supply terminal from ON to OFF is achieved.

Abstract: A switch includes at least two signal ports in series with a series FET connected therebetween, and a shunt path having an FET, whereby an input bias is applied to a gate on the series FET and to a drain on the shunt FET. In one embodiment, the switch includes a control signal input, an FET connected in series across the first port and the second port, the series FET having a gate coupled to the control signal input, and a shunt path provided by an FET, the shunt FET having a drain coupled to the control signal input and to the gate of the series FET, whereby a single control signal is applied to both the series FET and the shunt FET, via the control signal input, in order to turn the series FET on and simultaneously turn the shunt FET off and, conversely, in order to turn the series FET off and simultaneously turn the shunt FET on.

Abstract: A microwave switch array includes a plurality of microwave slotlines, each of which is controlled by a semiconductor switch including a first PIN junction formed by a primary P-type electrode and a primary N-type electrode separated by the slotline. The switches inject a plasma into the slotline in response to a potential applied across the first PIN junction. Each of the switches includes a second PIN junction between the primary P-type electrode and a secondary N-type electrode, and a third PIN junction between the primary N-type electrode and a secondary P-type electrode. Metal contacts connect the primary P-type electrode and the secondary N-type electrode across second PIN junction, and the primary N-type electrode and the secondary P-type electrode across the third PIN junction. The secondary electrodes extract plasma that diffuses away from the first PIN junction, thereby minimizing the performance degrading effects of plasma diffusion.

Abstract: A hybrid balun apparatus are disclosed. The hybrid balun apparatus can support both the reception mode and the transmission mode and be advantageous for a high level of integration, by replacing two transformers disposed at a reception path and a transmission path with a single transformer and integrating a T/R switch and a balun into a one chip. Therefore, an IC according to integration extends to a front stage of an antenna to facilitate interfacing between elements, and a burden for designing at a rear stage (i.e., LNA in the reception mode, and PA in the transmission mode) can be reduced.

Abstract: In view of achieving a cost reduction of an antenna switch, a technique is provided which can reduce harmonic distortion generated in the antenna switch as much as possible in particular even when the antenna switch is comprised of a field effect transistor formed over a silicon substrate. Each of a TX series transistor, an RX series transistor, and an RX shunt transistor is comprised of a low voltage MISFET, while a TX shunt transistor is comprised of a high voltage MISFET. Thus, by reducing the number of serial connections of the high voltage MISFETs constituting the TX shunt transistor, the nonuniformity of the voltage amplitudes applied to the respective serially-coupled high voltage MISFETs is suppressed. As a result, the generation of high-order harmonics can be suppressed.

Abstract: Techniques, apparatus and systems for a multiple pole multiple throw (MPMT) RF switch device based on composite left and right handed (CRLH) metamaterial structures.

Abstract: A high isolation electronic multiple pole multiple throw (MPNT) switching device is formed as a ring circuit that includes plural poles, plural throws, plural series switches and plural means for shunting. Each series switch receives a control signal, and each means for shunting receives shunt control signals. In one aspect, the shunt control signals include control signals received by distant series switches. In another aspect, the shunt control signals include control signals received by adjacent series switches. In another aspect, the shunt control signals include signals complementary to signals received by adjacent series switches. In another aspect, the shunt control signals include pole DC potentials or throw DC potentials. In another aspect, a switching device may operate in multiple transmission mode or multiple input multiple output (MIMO) mode. The MPNT switching device provides low insertion loss and high isolation at a wide range of frequencies.

Abstract: A ferroelectric varactor suitable for capacitive shunt switching is disclosed. High resistivity silicon with a SiO2 layer and a patterned metallic layer deposited on top is used as the substrate. A ferroelectric thin-film layer deposited on the substrate is used for the implementation of the varactor. A top metal electrode is deposited on the ferroelectric thin-film layer forming a CPW transmission line. By using the capacitance formed by the large area ground conductors in the top metal electrode and bottom metallic layer, a series connection of the ferroelectric varactor with the large capacitor defined by the ground conductors is created. The large capacitor acts as a short to ground, eliminating the need for vias. The varactor shunt switches can be used to create a bandpass filter and a tunable notch filter. The bandpass filter is implemented by cascading the switches, and the bandpass filter implemented through the use of a resonance circuit.

Abstract: A phase shifter selectively switches between a low-pass filter 13 and a high-pass filter 12 using single pole double throw switches 10a and 10b provided on the input and output sides, respectively, and operatively linked to each other. The single pole double throw switches 10a and 10b include FETs Q1c and Q1d that connect single pole side junctions and the low-pass filter, respectively, and inductance circuits (L1c and R2c, and L1d and R2d) connected in parallel with FETs Q1c and Q1d, respectively. The inductance circuits are respectively comprised of the inductor L1c and the resistor R2c connected in series and of the inductor L1 d and the resistor R2d connected in series.

Abstract: A transmit-receive switch has a transmit port, an antenna port, and a receive port. A first switch couples the transmit port to the antenna port when a signal TxON is asserted. A LOW_BAND signal indicates the selection of a lower band of frequencies. A tuning structure is formed by a second and third switch in series which couple the antenna port to ground through a first capacitor when TxON and LOW_BAND are both asserted, and LOW_BAND may be provided to one or more such tuning structures for multi-band frequency operation. A second capacitor couples the antenna port to ground when a fourth switch is enabled. An inductor couples the antenna port to the receive port. A third capacitor is placed across the receive port and ground. A fifth switch is closed when TxON is asserted. The first through fifth switches can be a CMOS FET with an isolated substrate coupled to ground through an associated resistor.

Abstract: A high frequency module for transmitting and receiving, for example, communication signals of GSM/DCS/PCS/WCDMA systems through a single antenna, is provided at a relatively small size and low cost. The high frequency module includes a diplexer arranged to separate communication signals from the antenna into GSM communication signals in lower frequency bands and POS/DOS/WODMA communication signals in higher frequency bands, a diode switch circuit that is connected to a input and output terminal of the GSM communication signal of the diplexer and is arranged to switch transmission and reception of the GSM communication signal, and a multipoint GaAsIC switch that is connected to the GSM/DCS/PCS/WCDMA communication signals of the diplexer and is arranged to switch transmission and reception of these signals. The high frequency module switches the four types of communication signals by changing the patterns of controls signals VcG, VC1, and Vc2 that are applied to the diode switch circuit and the GaAsIC switch.

Abstract: There are provided a semiconductor device and a semiconductor chip, in which the interconnection is made to be highly reliable by stacking three or more layers of chips without contact therebetween. A semiconductor chip of the present invention comprises a first signal transmission circuit, a silicon substrate on which a first changeover switch is formed, and an interconnection layer on which a first capacitive-coupling upper electrode is formed, wherein a first capacitive-coupling lower electrode is additionally formed on the rear surface of the silicon substrate through a first via hole that penetrates the silicon substrate and, whereas the first capacitive-coupling upper electrode is directly connected to the first signal transmission circuit, the first capacitive-coupling lower electrode is connected to the first signal transmission circuit through the first via hole and through the first changeover switch.

Abstract: A radio frequency (RF) transmit/receive switch. The transmit/receive switch comprises an impedance matching circuit and a voltage scaling circuit. The impedance matching circuit matches an incoming RF signal to a low noise amplifier and an outgoing RF signal from a power amplifier. The voltage scaling circuit, coupled to the impedance matching circuit, the power amplifier, and the low noise amplifier, attenuates the outgoing RF signal to a scaled signal within a breakdown voltage of a transistor device in the low noise amplifier during transmission of the outgoing RF signal.

Abstract: An exemplary embodiment of the present invention described and shown in the specification and drawings is a transceiver with a receiver, a transmitter, a local oscillator (LO) generator, a controller, and a self-testing unit. All of these components can be packaged for integration into a single IC including components such as filters and inductors. The controller for adaptive programming and calibration of the receiver, transmitter and LO generator. The self-testing unit generates is used to determine the gain, frequency characteristics, selectivity, noise floor, and distortion behavior of the receiver, transmitter and LO generator. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Abstract: RF switches are known from the art for selecting an RF signal from a multiple of inputs. For instance a TV-tuner and TV-Front-end can have two or more antenna inputs but are implemented with a relative bad cost performance. The present invention relates to an RF selection switch circuit (200). The switch comprises a first switch (202), a second switch (204) with both an RF input port and a common RF output port a control signal circuitry (206). In a preferred embodiment the switches comprise pin-diodes. The RF output port comprises two transistors (T1, T2), one of which at a time can put the non-selected switch to a low-impedance level in order to minimize signal leakage the common output port.

Abstract: A linear antenna switch arm comprising a plurality of field effect transistors connected in series, the drain of each transistor being connected to the source of the next transistor at a join, the end source comprising one of a signal input or output port and the end drain comprising the complementary signal output port or input port; a signal line extending between the input and output ports; at least one of the joins being connected to the signal line at a node by a connection line; the signal line comprising at least one resistor between signal input and output ports; and the connection line comprising at least one resistor.

Abstract: One high-frequency switch Qm supplied with transmit and receive signals to ON, and another high-frequency switch Qn supplied with a signal of another system to OFF are controlled. In the other high-frequency switch Qn, to set V-I characteristics of near-I/O gate resistances Rg1n-Rg3n of a near-I/O FET Qn1 near to a common input/output terminal I/O connected with an antenna are set to be higher in linearity than V-I characteristics of middle-portion gate resistances Rg3n and Rg4n of middle-portion FETs Qn3 and Qn4. Thus, even in case that an uneven RF leak signal is supplied to near-I/O gate resistances Rg1n-Rg3n, and middle-portion gate resistances Rg3n and Rg4n, the distortion of current flowing through the near-I/O gate resistances Rg1n-Rg3n near to the input/output terminal I/O can be reduced.

Abstract: A current steering mechanism is provided in a radio transmitter (e.g., a multiband radio transmitter) to provide compatibility with a variety of baseband parts. Different proportions of an input signal current (“in”) are steered to a dummy load, a mixer for a first band, and at least one other mixer for a second band. The mechanism is structured to selectively apportion a current input signal between multiple paths of the same polarity having respective load circuits and concurrently steer different proportions of the current input signal to a dummy load path and at least one mixer path.

Abstract: A switch circuit for passing or blocking a high-frequency signal includes a correction circuit for correcting an impedance component that exists in the switch circuit and that changes asymmetrically with the direct-current potential as a reference such that impedance as seen from either high-frequency terminal changes symmetrically with the direct-current potential as a reference in response to positive and negative changes that take the direct-current potential of the high-frequency signal as a reference.

Abstract: A transistor single-pole-single-throw circuit device includes at least a transistor single-pole-single-throw circuit having a first transistor and a second transistor, and an inductor capacitor (LC) resonator having an inductor and a capacitor connected in series, allowing two ends of the LC resonator connected to the first source and the first drain of the first transistor, respectively. The transistor single-pole-single-throw circuit device adopts an LC resonator having an inductor and a capacitor connected in series to connect with the first source and the first drain of the first transistor. The inductor couples and resonates with a parasitic capacitance of the transistor, to reduce signal loss due to emerged parasitic capacitance when the conventional single-pole-single-throw circuit selects a switch transistor with a larger width.

Abstract: Provided is a high-isolation switching device for a millimeter-wave band control circuit. By optimizing a cell structure to improve the isolation of an off-state without deteriorating the insertion loss of an on-state, it is possible to implement a high-isolation switching device useful in the design and manufacture of a millimeter-wave band control circuit such as a phase shifter or digital attenuator using switching characteristics. In addition, when a switch microwave monolithic integrated circuit (MMIC) is designed to use the switching device, it is not necessary to use a multi-stage shunt field effect transistor (FET) to improve isolation, nor to dispose an additional ?/4 transformer transmission line, inductor or capacitor near the switching device. Thus, chip size can be reduced, degree of integration can be enhanced, and manufacturing yield can be increased. Consequently, it is possible to reduce manufacturing cost.

Abstract: The present invention provides an RF switch, including a diode adapted to operate as a switch when a control current is applied thereto, a first CRLH transmission line of a ? degree phase, which provides one signal transfer path from a terminal 1 to a terminal 2 when the diode is shorted due to application of a control current, and a second CRLH transmission line of a ?-180 degree phase, which has a 180 degree phase difference from that of the first CRLH transmission line and provides the other signal transfer path from the terminal 1 to the terminal 2. The present invention provides an RF switch having a broad-band characteristic by employing a CRLH transmission line. More specifically, the present invention provides a ring-shaped RF switch, which has a broad-band characteristic and can also be miniaturized at a low frequency band, by employing a CRLH transmission line having a 180 degree phase difference in a broad band.

Abstract: A low-loss Radio Frequency (RF) switch for high-power RF signals. The RF switch includes a first-biasing circuit connected to a first transistor and a second-biasing circuit connected to a second transistor. The RF switch switches its output signal between a first input signal and a second input signal. The first transistor is in a conduction state and the second transistor is in a non-conduction state when the first input signal is to be conducted to the output signal. The first-biasing circuit biases the first transistor at a first voltage for increasing conduction of the first input signal and the second-biasing circuit biases the second transistor at a second voltage for decreasing conduction of the first input signal. Moreover, the second transistor is in a conduction state and the first transistor is in a non-conduction state when the second input signal is to be conducted to the output signal.

Abstract: A single pole N throw (SPNT) switch arrangement including: a pole, one or more throw nodes and a switch mechanism arranged to connect the pole and a first throw node in response to a first signal and to disconnect the pole and the first throw node in response to a second signal; an interconnect, for providing the first signal, arranged for connection to the pole when providing the first signal; and a dc power source arranged to control a dc bias applied to the interconnect to provide the first signal

Abstract: A broadband, high-speed RF step attenuator implemented using long-lifetime PIN diode switches is presented which provides step attenuation across a significant portion of the entire RF frequency spectrum while maintaining minimal insertion loss, return loss, and harmonics.

Abstract: A single pole single throw switch for controlling propagation of a high frequency signal between an input terminal (11a) and an output terminal (11b). First FET switches (14a, 14b) in which drains and sources of FETs (12a, 12b) are connected in parallel with inductors (13a, 13b) are connected in parallel. Each FET (12a, 12b) is switched between on state and off state by a voltage being applied to the gate thereof. At the frequency of the high frequency signal, each inductor (13a, 13b) connected with off capacitor of each FET (12a, 12b) resonates in parallel.

Abstract: A four-state digital attenuator for an RF signal includes a first external terminal adapted to receive a first control voltage; a second external terminal adapted to receive a second control voltage, and a third external terminal connected to a fixed supply voltage. The four-state digital attenuator receives no supply voltages other than the control voltages and the fixed supply voltage connected to the third external terminal. A plurality of series paths are provided from an RF input to an RF output, each of the series paths passing through a node. A plurality of shunt paths are provided from the node to the third external terminal. A driver selectively enables the series paths and shunt paths in response to the first and second control voltages to provide four attenuation levels for an RF signal from the RF input to the RF output.

Abstract: A switching circuit includes switching transistors connected to one of an input terminal and an output terminal of the switching circuit, and a control bias supply circuit that supplies a control bias for cutting off all the switching transistors to the switching transistors when all of the switching transistors are in a non-selected state.

Abstract: A RF transceiver includes an antenna, a receiver, a baseband circuit, a transmitter, and a T/R switch circuit. The T/R switch circuit is used for coupling the antenna and the receiver or coupling the antenna and the transmitter. The T/R switch circuit is coupled to the baseband circuit so as to receive biases provided from the baseband circuit. The T/R switch circuit includes four transistors and a power detector. The power detector detects the power of the output signal of the T/R switch circuit, so that the baseband circuit can adjust biases provided to the T/R switch circuit according to the power of the output signal.

Abstract: A branch path having a transmission line and a distributed constant line includes a resonant circuit. The resonant circuit resonates at a predetermined operating frequency when the branch path is in OFF state. At this time, the distributed constant line has a predetermined impedance. Further, an impedance of a node between the resonant circuit and distributed constant line can be set on a circle of a reflection coefficient 1 near short on the Smith chart.

Abstract: An RF switch circuit (10) and a tuner (12) comprising an RF switch circuit are described. The switch circuit comprises at least two input terminals and one output terminal. The input terminals are connected to different RF signal sources, e. g. a terrestrial TV antenna (16) and a TV cable network (18). The circuit comprises first SPST switches (28, 30), each connected to one of the input terminals and a second, SPDT switch (32) connected to the first SPST switches. The switch circuit achieves high isolation performance between the input terminals (20, 22).