Abstract: An apparatus includes a digitally controlled oscillator (DCO), which includes an inductor coupled in series with a first capacitor. The DCO further includes a second capacitor coupled in parallel with the series-coupled inductor and first capacitor, a first inverter coupled in parallel with the second capacitor, and a second inverter coupled back-to-back to the first inverter. The DCO further includes a digital-to-analog-converter (DAC) to vary a capacitance of the first capacitor.

Abstract: An apparatus includes a digitally controlled oscillator (DCO), which includes an inductor coupled in series with a first capacitor. The DCO further includes a second capacitor coupled in parallel with the series-coupled inductor and first capacitor, a first inverter coupled in parallel with the second capacitor, and a second inverter coupled back-to-back to the first inverter. The DCO further includes a digital-to-analog-converter (DAC) to vary a capacitance of the first capacitor.

Abstract: A TV tuner includes an Ultra High Frequency (UHF)/Very High Frequency (VHF) tracking filter, an UHF/VHF matching circuit and a single conversion Tuner IC. The UHF/VHF tracking filter includes a first Low-Temperature Co-fired Ceramics (LTCC) inductor, a first varactor diode and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF tracking filter. The UHF/VHF matching circuit includes a second LTCC inductance, a second varactor diodes and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF matching circuit.

Abstract: A TV tuner includes an Ultra High Frequency (UHF)/Very High Frequency (VHF) tracking filter, an UHF/VHF matching circuit and a single conversion Tuner IC. The UHF/VHF tracking filter includes a first Low-Temperature Co-fired Ceramics (LTCC) inductor, a first varactor diode and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF tracking filter. The UHF/VHF matching circuit includes a second LTCC inductance, a second varactor diodes and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF matching circuit.

Abstract: Embodiments of the invention may be directed to a continuous analog phase shifter for radio frequency (RF) signals, which can be integrated on a CMOS process or another compatible process where inherent process-dependent passive components such as inductors and capacitors may have low quality factors. Insertion loss degradation for a given amount of phase shift may be compensated by using an active compensation circuit/device that smartly controls negative resistance generated from the compensation circuit/device to cancel out finite resistance of a network, leading to very small insertion loss variation. According to an example aspect of the invention, improved phase linearity and increased phase shift for a given size may be obtained by incorporating the compensation circuit/device. Thus, example analog phase shifters in accordance with example embodiments of the invention may have one or more of low insertion loss variation, small size, and good phase linearity over more than a 360 degree phase shift.

Abstract: A TV tuner includes an Ultra High Frequency (UHF)/Very High Frequency (VHF) tracking filter, an UHF/VHF matching circuit and a single conversion Tuner IC. The UHF/VHF tracking filter includes a first Low-Temperature Co-fired Ceramics (LTCC) inductor, a first varactor diode and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF tracking filter. The UHF/VHF matching circuit includes a second LTCC inductance, a second varactor diodes and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF matching circuit.

Abstract: Implementations of differential variable capacitance systems are disclosed.

Abstract: A system and method for sharing a switched capacitor array (SCA) by two tuning circuits are disclosed. In a multiple-band radio receiver, there is a need to use multiple tuning circuits for signals in different bands. The tuning circuit typically comprised an adjustable capacitance device and other tuning components, where the adjustable capacitance device is often implemented in SCA. The present invention discloses a system and method comprising n sections of capacitor elements where each capacitor element comprises a capacitor and switches to selectively connect the capacitor to one of the tuning circuit. Consequently, the SCA can be shared by the two tuning circuits. The control bits for the switched may be provided from a programmable control register.

Abstract: A TV tuner includes an Ultra High Frequency (UHF)/Very High Frequency (VHF) tracking filter, an UHF/VHF matching circuit and a single conversion Tuner IC. The UHF/VHF tracking filter includes a first Low-Temperature Co-fired Ceramics (LTCC) inductor, a first varactor diode and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF tracking filter. The UHF/VHF matching circuit includes a second LTCC inductance, a second varactor diodes and a fine-tune capacitor electrically connected to determine the maximum gain frequency of the UHF/VHF matching circuit.

Abstract: One exemplary tunable capacitive device includes a first tunable capacitive element, a first coupling capacitive element, a first coupling resistive element, and a first specific capacitive element. The first tunable capacitive element has a first node coupled to a first input voltage, and a second node. The first coupling capacitive element has a first node coupled to the second node of the first tunable capacitive element, and a second node coupled to a first connection terminal of the tunable capacitive device. The first coupling resistive element has a first node coupled to the second node of the first tunable capacitive element, and a second node coupled to a second input voltage, where the first input voltage and the second input voltage include a control voltage and a reference voltage. The first specific capacitive element is coupled between the first node and the second node of the first tunable capacitive element.

Abstract: Structurally simple transmit/receive circuits for hearing devices are to be able to be deployed for higher frequencies as well. It is therefore proposed according to the invention that at least two PIN diodes should be connected in an anti-parallel manner between the receive oscillating circuit and the amplifier connected thereto to protect the amplifier. A capacitance diode can optionally be expanded so that larger component tolerances can be permitted for the circuit.

Abstract: A system, apparatus and/or method provides frequency response adjustment of an RF input filter of an RF tuner based on impedance of an antenna system that is providing reception of RF signals to the RF tuner. The frequency response adjustment is preferably accomplished dynamically and/or with respect to each frequency tuned. Particularly, the system, method and/or apparatus provides compensation at the RF tuner level for mistuning effects produced on the RF tuner by antenna system impedance presented at the antenna input that is other than a designed for impedance. Frequency response of an RF input filter for the RF tuner is electronically adjustable with an independent or semi-independent control voltage signal based on one or more measured parameters of a tuning frequency. Frequency response adjustment may include adjustment of a center frequency of the RF input filter bandpass frequency range and/or altering the bandpass frequency range of the RF input filter.

Abstract: In a double-tuning circuit including a primary tuning circuit having a first inductor and a first variable capacitive element connected in parallel and a secondary tuning circuit having a second inductor and a second variable capacitive element connected in parallel, a fixed part of a copper-foil pattern is connected to a connection point at which the double-tuning circuit is connected to an input terminal of a frequency mixing circuit, and a tip part of the copper-foil pattern extends to near the first inductor, whereby a trap circuit for attenuating an image frequency component is formed. A pattern is formed between a ground-side terminal of the first inductor and the ground, and a capacitor is connected between a connection point at which the first inductor is connected to one terminal of the pattern and a ground-side terminal of the second variable capacitive element.

Abstract: A system, apparatus and/or method provides frequency response adjustment of an RF input filter of an RF tuner based on impedance of an antenna system that is providing reception of RF signals to the RF tuner. The frequency response adjustment is preferably accomplished dynamically and/or with respect to each frequency tuned. Particularly, the system, method and/or apparatus provides compensation at the RF tuner level for mistuning effects produced on the RF tuner by antenna system impedance presented at the antenna input that is other than a designed for impedance. Frequency response of an RF input filter for the RF tuner is electronically adjustable with an independent or semi-independent control voltage signal based on one or more measured parameters of a tuning frequency. Frequency response adjustment may include adjustment of a center frequency of the RF input filter bandpass frequency range and/or altering the bandpass frequency range of the RF input filter.

Abstract: A radio frequency tuner comprises one or more tracking filters ahead of at least one frequency changer. A controller has a filter alignment mode and a reception mode. Each filter has one or more resonant networks comprising an inductance and a switched capacitor network which is digitally controlled for selecting the network resonant frequency. In the alignment mode, the controller determines the difference between the nominal and actual capacitances of the network for achieving a known resonant frequency in order to determine a correction factor for the capacitor network. The correction factor is then used during normal reception by the tuner.

Abstract: A communications device including communications circuitry, tunable filter circuitry including a node configured to pass a signal between an antenna and the communication circuitry, and control circuitry configured to cause energy in the tunable filter circuitry to be adjusted for a time period and configured to determine a resonant frequency of the tunable filter circuitry from oscillations on the node caused by the energy subsequent to the time period is provided.

Abstract: Disclosed herein is a system for the variable attenuation of broadband differential signals. An exemplary system of variable attenuation of broadband differential signals includes attenuation devices arranged such that an attenuation device on the positive side of the differential signal has a corresponding attenuation device on the negative side of the differential signal with both of the corresponding attenuation devices on the same semiconductor die.

Abstract: A voltage controlled oscillator (VCO), suitable for use in a frequency shift keying (FSK) system. The VCO device comprises a switching varactor unit, having a first terminal and a second terminal, wherein the switching varactor unit produces a capacitance, according to a frequency-selection voltage. A VCO core has a first output terminal, a second output terminal complementary to the first output terminal, and an input terminal. Wherein, the switching varactor unit is coupled in parallel with the VCO core at the first output terminal and the second output terminal to produce a capacitance effect with respect to the capacitance, so as to adjust a frequency constant ?{square root over (LC)} of the VCO core.

Abstract: The present invention provides to provide a television tuner capable of improving image disturbance when receiving a UHF band television signal. The television tuner comprises a tuning circuit having a tuning circuit having two varactor diodes connected in series with a connection point between the two varactor diodes serving as an output terminal and a coupling inductive element having its one end connected to an input terminal of the tuning circuit and the other end connected to an input terminal of an television signal. One varactor diode is connected to the input terminal of the tuning circuit, the other varactor diode is interposed between the output terminal and a ground, and a first capacitive element is connected between the other end of the inductive element and the connection point between the two varactor diodes.

Abstract: A band switchable type tuning circuit has first switch means interposed between a power supply Vcc and an anode of a switch diode, a first resistor whose one end is connected to a cathode of the switch diode, second switch means interposed between the other end of the first resistor and a ground, a second resistor connected between the power supply Vcc and a connection point of the first resistor and the second switch means, and the third resistor connected between the ground and a connection point of the first switch means and the anode of the switch diode. The first switch means and the second switch means are turned on or off together by means of a band switching voltage.

Abstract: An electronic tuning system includes an electronic tuner for adjusting the predetermined control voltage of a voltage controlled oscillator (VCO) to tune the local frequency signal to radio waves on an arbitrary channel in accordance with channel selection information. A booster circuit boosts a source voltage to generate a boosted voltage in order to ensure the predetermined control voltage. A non-volatile memory stores the channel selection information in response to a predetermined write voltage. The boosted voltage of the booster circuit is utilized as the predetermined write voltage.

Abstract: The present invention provides a means for improving the sensitivity and selectivity of a car radio receiver. The variable inductance LC resonant circuit comprises: a amplifier 53 having enough high input impedance and enough low output impedance, a inductive element 51 connected a terminal to the input of said amplifier 53 and the other terminal to the output terminal of said amplifier 53, and a capacitive element 52 connected a terminal to the input terminal of said amplifier 53 and the other terminal to the ground. The proposed technique alters the parallel resonant frequency by varying an equivalent inductance 51, 53 seen from the condenser 52 side, wherein the equivalent inductance 51, 53 varies associated with the gain of said amplifier depending on the frequency control voltage from the PLL synthesizer to the terminal 54.

Abstract: The invention proposes a device for high-frequency and/or radio-frequency tuning comprising within one IC-package a first variable capacitor (C1) and at least one second capacitor (C2), each of the at least one second capacitor (C2) being fixed or variable respectively, at least one signal path connected to the first variable capacitor (C1) and providing at least one input and one output port (rf-port1, rf-port2) and at least one controllable switching means (SC2) for individually connecting and disconnecting at least one of the at least one second capacitor (C2) into the signal path or from the signal path, in particular in parallel to the first variable capacitor (C1).

Abstract: A communication system (8) for transmitting data between cores (10) embedded in an integrated circuit on a silicon chip (12). Communication system (8) includes transmitter circuitry (24) for wirelessly transmitting data between cores (10) and receiver circuitry (26) for wirelessly receiving the transmission of data from other cores. Both transmitter circuitry (24) and receiver circuitry (26) may include of a phase-locked loop circuit (28, 30) having a voltage-controlled oscillator (36). Each core (10) may transmit and receive data on a unique frequency with respect to other cores embedded in an integrated circuit on a silicon chip (12) or transmit and receive data on the same frequency as other cores embedded in an integrated circuit on a silicon chip (12). Groups of cores (17) may share transmitter and receiver circuitry (24 and 26).

Abstract: A frequency translating device (FTD) includes at least one mixer diode connected to down-convert a radio frequency (RF) to an intermediate frequency (IF) and to up-convert an IF to an RF and a source of direct current (DC) bias that is connected to the mixer diode. The source of DC bias provides DC bias to the mixer diode that moves the voltage applied to the mixer diode closer to the threshold voltage of the mixer diode. The mixer diode is turned on in response to the DC bias and a local oscillator (LO) drive. Because DC bias is applied to the mixer diode, the peak to peak voltage range of the LO drive can be reduced, thereby reducing the voltage-dependent capacitance of the mixer diode, causing the FTD to exhibit improved reciprocity. The FTD can be used in a three-pair measurement system to determine the conversion response of another FTD.

Abstract: Linearizer circuitry is disclosed for providing control signal outputs to operate a controllable attenuator throughout a relatively large dynamic range while maintaining a relatively consistent return loss. Preferred embodiment linearizer circuitry provides a series control current and a shunt control current for coupling to a PIN diode attenuator, such as may be configured in a ? network or a T network. Preferably, differential pairs are utilized in providing each of the control current outputs.

Abstract: Method for tuning the reception of radio broadcast signals to an FM RDS transmitter using program related data and transmitter related data and receiver executing the method, providing a band scanning search for detecting FM RDS transmitters exceeding a predetermined reception quality level. To enhance efficiency in data processing and use of storage capacity, transmitter related data including tuning data is stored separately from program related RDS data. Per each detected transmitter a permanency factor indicating the permanency in reception quality thereof is being allocated to each detected RDS transmitter and stored in a first memory bank, along with the relevant tuning data.

Abstract: A gain deviation is leveled in the same band by using a varactor diode having the same characteristics as that used in an input tuning circuit for coupling the input tuning circuit and a high frequency amplifier The input tuning circuit has a tuning varactor diode whose tuning frequency varies with a tuning voltage applied to the cathode of the tuning varactor diode, a high-frequency amplifier is provided in a stage subsequent to the input tuning circuit, and a coupling varactor diode for coupling the input tuning circuit to the high-frequency amplifier, in which the cathode of the coupling varactor diode and that of the tuning varactor diode are connected with each other and a bias voltage higher than the voltage at the anode of the tuning varactor diode and lower than the lowest voltage of the tuning voltage is applied to the anode of the coupling varactor diode.

Abstract: A voltage controlled LC resonance oscillation circuit has a plurality of capacitive elements connected to an output node. These capacitive elements are applied with voltages at opposing terminals for selecting an oscillating frequency band, so that the oscillating frequency band can be changed step by step in accordance with the selection voltage. The capacitive elements include at least one variable capacitive element such as a MOS capacitor, the capacitance of which is varied in accordance with a voltage applied thereto. The MOS capacitor is similar in structure to a MOS transistor. The variable capacitive element can be supplied at a terminal opposite to the output node with a voltage from a variable voltage source, for example, in place of the selection voltage. The voltage controlled LC resonance oscillation circuit can measure the output amplitude and oscillating frequency without affecting the characteristics thereof, and reduce the parasitic capacitance.

Abstract: A high-frequency-signal switching circuit includes a first high-frequency-signal path which includes first and second diodes connected in series with a high-frequency amplifier stage therebetween, and a second high-frequency-signal path formed of a third diode connected in parallel to the first high-frequency-signal path. A switching-voltage supply section switches the high-frequency amplifier stage and first and second diodes ON, and the third diode OFF, so that a high-frequency signal is transferred through the first high-frequency-signal path, or switches the high-frequency amplifier stage and first and second diodes OFF and the third diode ON, so that a high-frequency signal is transferred through the second high-frequency-signal path.

Abstract: For tuning an LC resonator (2) which particularly comprises a miniaturized antenna coil (LA), a variable capacitance (CT) is connected in parallel to the LC resonator (2). At manufacturing time, a maximum resonance frequency of the LC resonator (2) is measured when the variable capacitance (CT) is set to its minimum value, a minimum resonance frequency of the LC resonator (2) is measured when the variable capacitance (CT) is set to its maximum value, and coded values of the measured maximum and minimum resonance frequencies are stored in non-volatile memories (Fmin, Fmax). At operations time, a binary tuning code (B) is computed as a linear interpolation between the stored values of the minimum and maximum resonance frequencies for a target resonance frequency (ft). The LC resonator (2) is tuned to the target resonance frequency (ft) by selectively connecting separate binary weighted capacitors (Cn−1, . . .

Abstract: Method for processing transmitter and program related data in an FM RDS receiver and receiver executing the method, providing a band scanning search for detecting FM RDS transmitters exceeding a predetermined reception quality level. To enhance efficiency in data processing and use of storage capacity, transmitter related data including tuning data is stored separately from program related RDS data. Per each detected transmitter a quality factor indicating the quality in reception quality thereof is being allocated to each detected RDS transmitter and stored in a first memory bank, along with the relevant tuning data.

Abstract: The present invention resides in the provision of an intermediate frequency circuit in a television tuner capable of enlarging the attenuation of a audio IF carrier in an adjacent channel without increasing a loss in an intermediate frequency band. The intermediate frequency circuit comprises a mixer which outputs an intermediate frequency signal, an intermediate frequency amplifier for amplifying the intermediate frequency signal outputted from the mixer 1, and a feedback circuit disposed between an input end and an output end of the intermediate frequency amplifier, and in the intermediate frequency circuit, a audio IF carrier of an adjacent intermediate frequency signal adjacent to the intermediate frequency signal is fed back from the output end to the input end of the intermediate frequency amplifier by the feedback circuit.

Abstract: The invention relates to a resonator (200,300) with variable resonance frequency, intended for connection to an amplifier, thus forming an oscillator, said resonator comprising a resonator circuit (205,305) for deciding the resonance frequency of the resonator and the oscillator, said resonator circuit comprising an inductance (L), a variable capacitance (Cj), and means (Vtune) for varying the capacitance. The resonator also comprises connection means (C1, Ck; C1, Ck, C2) for connecting the resonator to an amplifier. The resonator is provided with means (Vtune) for varying the capacitance of the connection means in proportion to the variation of the capacitance (Cj) of the resonator circuit. Preferably, the means (Vtune) for varying the capacitance (Ck) of the connection means are arranged such that an essentially constant relationship (Ck/Cj) is maintained between the capacitance (Ck) of the connection means and the first capacitance (Cj) of the resonator across all resonance frequencies.

Abstract: An electronic tuning system includes an electronic tuner for adjusting the predetermined control voltage of a voltage controlled oscillator (VCO) to tune the local frequency signal to radio waves on an arbitrary channel in accordance with channel selection information. A booster circuit boosts a source voltage to generate a boosted voltage in order to ensure the predetermined control voltage. A non-volatile memory stores the channel selection information in response to a predetermined write voltage. The boosted voltage of the booster circuit is utilized as the predetermined write voltage.

Abstract: Between one end of a high-band tuning coil in a primary tuning circuit and one end of a high-band tuning coil in a secondary tuning circuit, a first switch diode and a second switch diode connected in series are provided. A second coupling coil is provided between the ground and the connection point of the first switch diode and the second switch diode. Both first switch diode and second switch diode are set to a continuity state or a non-continuity state to switch between a high-band state and a low-band state.