Abstract:
PROBLEM TO BE SOLVED: To provide a voltage-controlled oscillator with an output maintained at a constant level at all times independently of the oscillated frequency. SOLUTION: The voltage-controlled oscillator 1a includes: a voltage-controlled oscillation circuit VCO for oscillating the frequency in response to a control voltage; and a limiter circuit LMT placing a limit of a prescribed level to an output of the voltage-controlled oscillation circuit VCO. COPYRIGHT: (C)2004,JPO
Abstract:
PURPOSE: To suppress as much as possible the fluctuation of frequency against power supply voltage fluctuation by using a bipolar transistor in common base connection in terms of high frequencies and loading an externally mounted capacitance circuit between the collector and emitter of the transistor. CONSTITUTION: Fig. shows a Colpitts oscillation circuit using a common base transistor connection. A fixed capacitor 17 is used as a load to the circuit shown in Fig. Through the constitution above, suppose that a collector capacitance having a varactor element function in a conventional circuit is increased by ΔC 1 from the initial capacitance C 1 due to power supply fluctuation, the rate of change is expressed as ΔC 1 /C 1 , and the equivalent capacitance ratio is ΔC 1 / (C 1 +C 2 ) by loading the fixed capacitor 17 of a capacitance C 2 between the collector 13 and base 14, that is, in parallel with the collector capacitance, the effective sensitivity is decreased and the rate of change in the capacitance against the power supply voltage is reduced. COPYRIGHT: (C)1985,JPO&Japio
Abstract:
PURPOSE: To make it possible to obtain superior oscillation characteristics even in super and hyper bands by increasing and oscillating a feedback voltage of an emitter at a low area of an oscillation frequency band having a large capacity value of a tuning diode. CONSTITUTION: The titled oscillator circuit is a clapp oscillator circuit generally used for a tner. A capacitor 17 is connected between the emitter of an oscillating transistor(TR) 1 and a connection point between a tuning diode 10 of a tank circuit and a capacitor 11 for compensating an oscillation frequency changing range. The capacitor 17 compensates the oscillation voltage, a feedback amount outputted from the emitter of the TR1 at the feedback from the base to the emitter of the TR1 by a base feedback capacitor 8 and a coupling capacitor 9 consisting of the TR1 and the tank circuit. COPYRIGHT: (C)1984,JPO&Japio
Abstract:
PURPOSE:To make the circuit light and small and to adjust the modulation factor, by providing a hollow coupling element metallizing the inner surface coupled with a resonator in a dielectric substance and connecting one end of the coupling element to an external circuit. CONSTITUTION:A high dielectric constant dielectric substance 1 incorporates a resonance circuit and a coupler, it is cylindrical and the circular surface is metallized. The inner surface of a hollow section 2 is metallized, it acts like as a both end opened-TEM mode resonator, and the base of a transistor oscillating element 3 is coupled with the resonator 1 with a coupling element 4. A varactor 7 is coupled to another end of the resonator 1, a modulation voltage V is applied to the varactor and the frequency modulation for the oscillated frequency is made as a voltage controlled oscillator by changing the varactor capacitance.
Abstract:
Methods and means related to an electronic circuit having an inductor and a memcapacitor are provided. Circuitry is formed upon a substrate such that an inductor and non-volatile memory capacitor are formed. Additional circuitry can be optionally formed on the substrate as well. The capacitive value of the memcapacitor is adjustable within a range by way of an applied programming voltage. The capacitive value of the memcapacitor is maintained until reprogrammed at some later time. Oscillators, phase-locked loops and other circuits can be configured using embodiments of the present teachings.
Abstract:
A phase locked loop (PLL) system, comprises: a voltage controlled oscillator (VCO) circuit (308), comprising a first plurality of switchable varactors (604) for selecting a frequency band of the VCO, that has a gain that changes with frequency band, and a second plurality (606) of switchable varactors for varying the gain in the selected band. The PLL system has a PLL feedback circuit (324) comprising a switching device (302) for switching the feedback circuit (324) to an open loop state wherein a plurality of predefined tuning voltages (320) can be applied to the VCO; a frequency measurement device (304) for measuring the synthesized VCO frequency (310); and a control unit (306) operable to determine the gain with respect to the synthesized frequency (310) and the tuning voltages (320).
Abstract:
Disclosed herein are embodiments of an LC-type VCO with multiple operational frequency bands having reasonably similar frequency vs. control signal slopes.
Abstract:
A feedback oscillator device (10) formed with an integrated circuit having a semiconductor material substrate on a ground plane. The circuit has an amplifier (17) having an input and an output is provided at least in part on said semiconductor material substrate. A directional coupler (18) is used to couple the amplifier output signal to the amplifier input through a parallel separated transmission lines (18', 18'') transfer system and a capacitor such as a varactor (21). The substrate can be of gallium arsenide.
Abstract:
A frequency-adjustable oscillator suitable for digital signal clock synchronization comprises a SAW oscillator circuit for generating an analog controlled-frequency signal and a sinewave-to-logic level translator circuit in a double-sided package. The SAW oscillator circuit includes a tunable SAW resonator, a gain stage for energizing the SAW resonator, a voltage-variable control input for adjusting a frequency of the controlled-frequency signal, and a voltage-variable capacitive element operably linked to the SAW resonator and responsive to the control input. The sinewave-to-logic level translator circuit is operably linked to the SAW oscillator circuit and configured to generate a digital logic output signal having substantially the same frequency as the controlled-frequency output signal. The double-sided package includes a platform with sidewalls extending substantially upwardly to form a first cavity adapted to receive and electrically connect the SAW resonator and sidewalls extending substantially downwardly to form a second cavity adapted to receive and electrically connect at least one electronic component. A cover is coupled with the first cavity to create an isolated environment for containing the SAW resonator.