Abstract:
A device comprises a first capacitor block comprising a plurality of first capacitors connected in a first configuration, a second capacitor block comprising a plurality of second capacitors connected in the first configuration, a third capacitor block comprising a plurality of third capacitors connected in a second configuration, a fourth capacitor block comprising a plurality of fourth capacitors connected in the second configuration, a first switch connected between the first capacitor block and the second capacitor block, a second switch connected between the third capacitor block and the fourth capacitor block, a third switch connected between the first capacitor block and the fourth capacitor block and a fourth switch connected between the third capacitor block and the second capacitor block.
Abstract:
A tunable impedance circuit can include a fixed impedance and one or more impedance selection circuits. Each impedance selection circuit can include a first impedance connected to a first interface terminal, a second impedance connected to a second interface terminal, and a plurality of series-connected transistors connected between the first and second impedances. Each impedance selection circuit can also include a plurality of drive impedance networks connected to gates, sources, drains, bodies, and isolation regions of the series-connected transistors, and a control circuit to provide a plurality of control signals to the drive impedance networks to turn on and turn off the series-connected transistors. For each impedance selection circuit, turning on and turning off the respective plurality of series-connected transistors can bring the series combination of the respective first and second impedances into and out of electrical communication with, e.g., into and out of parallel with, the fixed impedance.
Abstract:
An oscillator includes a first VCXO and a second VCXO which are capable of changing an output frequency by application of a control voltage, and a control voltage terminal to which the control voltage is applied, the first VCXO includes a variable-capacitance diode (first variable-capacitance diode) and a resistor (first resistor), the second VCXO includes a variable-capacitance diode (second variable-capacitance diode) and a resistor (second resistor), the cutoff frequency of the first variable-capacitance diode, the second variable-capacitance diode, the first resistor, and the second resistor is equal to the cutoff frequency of the first variable-capacitance diode and the first resistor, and the cutoff frequency of the second variable-capacitance diode and the second resistor.
Abstract:
An oscillation circuit includes a temperature compensating section to which electric power is supplied from a main power supply and a backup power supply, an oscillating section, a function of which is compensated by a signal from the temperature compensating section, and a switch and a power-supply monitoring circuit configured to select, when the temperature compensating section is not operating, at least one of the main power supply and the backup power supply and control connection to the temperature compensating section.
Abstract:
A device comprises a first variable capacitance block comprising four first capacitors, a second variable capacitance block comprising four second capacitors, wherein the second capacitors are arranged in a same configuration as the first capacitors, a third variable capacitance block comprising four third capacitors, a fourth variable capacitance block comprising four fourth capacitors, and wherein the fourth capacitors are arranged in a same configuration as the third capacitors, a first switch coupled between the first variable capacitance block and the second variable capacitance block, a second switch coupled between the third variable capacitance block and the fourth variable capacitance block, a third switch coupled between the first variable capacitance block and the fourth variable capacitance block and a fourth switch coupled between the third variable capacitance block and the second variable capacitance block.
Abstract:
One feature pertains to a digitally controlled oscillator (DCO) that comprises a variable capacitor and noise reduction circuitry. The variable capacitor has a variable capacitance value that controls an output frequency of the DCO. The variable capacitance value is based on a first bank capacitance value provided by a first capacitor bank, a second bank capacitance value provided by a second capacitor bank, and an auxiliary bank capacitance value provided by an auxiliary capacitor bank. The noise reduction circuitry is adapted to adjust the variable capacitance value by adjusting the auxiliary bank capacitance value while maintaining at least one of the first bank capacitance value and/or the second bank capacitance value substantially unchanged. Prior to adjusting the variable capacitance value, the noise reduction circuitry may determine that a received input DCO control word transitions across a capacitor bank sensitive boundary.
Abstract:
An integrated oscillator circuit comprises an oscillator configured to be switched between a first frequency and a second frequency. A switching circuit receives an input representing a target frequency and switches the oscillator between the first and second frequencies at intervals determined by the input, so as to cause the average output frequency of the oscillator to approximate the target frequency.
Abstract:
An oscillator includes: oscillation units (11 through 1n) outputting oscillation signals of different frequencies; a transmission line (15) to which outputs of the oscillation units (11, 12) are connected, the transmission line having a characteristic impedance corresponding to an output impedance of an output terminal (Tout); and a low-pass filter 818) connected between the transmission line (15) and the output terminal.
Abstract:
Aspects of a method and system for frequency tuning based on characterization of an oscillator are provided. In this regard, a frequency of an oscillator in an integrated circuit may be controlled based on a first digital control word, a frequency of a tuned circuit may be controlled based on a second digital control word, and the second control word may be determined utilizing a mapping between the first control word and the second control word. The frequency of the oscillator and the tuned circuit may be controlled by adjusting a capacitance of the oscillator and tuned circuit, respectively. The mapping may be based on a relationship between the oscillator and the tuned circuit, such as logical and/or mathematical relationship between the capacitance of the oscillator and the capacitance of the tuned circuit and/or the relationship between the frequency of the oscillator and the frequency of the tuned circuit.
Abstract:
An inductor circuit includes a pair of inductors connected in parallel with each other and a switch for turning on and off electric power to one of the pair of inductors. The inductance of the inductor circuit can be varied and the quality factor Q can be improved. Further, RF circuits employing the inductor circuit can generate an intended operating frequency.