摘要:
A variable capacitance device includes a ferroelectric capacitor, a control terminal, a ground terminal, and a capacitor. The ferroelectric capacitor includes a ferroelectric film and capacitor electrodes sandwiching the ferroelectric film, and its capacitance value is changed according to a control voltage value applied between the capacitor electrodes. The control terminal is connected to a first end of the ferroelectric capacitor. The ground terminal is connected to a second end of the ferroelectric capacitor. The capacitor is connected between the control terminal and the ground terminal, and has a capacitance larger than that of the ferroelectric capacitor.
摘要:
An ultra-high-frequency notch filter (100) comprises a capacitor (102) defining a conductive trace (106) on its body (103) and extending between its terminals (104). The trace has an inductance that forms a parallel LC circuit with the capacitance of the capacitor. When mounted on a printed circuit board (120) to connect two segments of a signal line (124), the notch filter and a ground plane (122) of the PCB form a virtual conductive loop having an inductance and a capacitance whose product is the center frequency of the notch of the notch filter. The center ferquency is tuned by varying the width of the trace.
摘要:
A circuit structure may include first and second transmission lines, each with a center conductor extending along or between one or more spaced-apart conducting surfaces. A conducting surface, such as a ground, reference, or signal-return plane, of the first transmission line may have an orientation that is transverse to the orientation of a conducting surface of the second transmission line. Each of the conducting surfaces of the first transmission line may contact one or more of the conducting surfaces of the second transmission line. In some examples, one or both of the transmission lines are slablines, and in some examples, the contacting edges or edges adjacent the contacting edges of the respective conductive surfaces are curved.
摘要:
An MCM including a resonator made using conventional MCM fabrication techniques. The MCM's resonator is constructed with overlapping first and second spiral-shaped regions of metallic material separated by a layer of dielectric material. A via disposed in the layer of dielectric material, couples the spiral-shaped regions of metallic material together, thereby utilizing self winding and internal capacitance to gain resonance at frequencies between 500 MHz to 3GHz. The internal capacitance is increased by controlling the overlap between the first and second spiral-shaped regions of metallic material. On a high-resistivity substrate, the monolithic resonator achieves a Q of at least 19 at approximately 900MHz and at least 24 at approximately 2GHz.
摘要:
A multilayer microelectronic circuit to be directly mounted on a substrate and to be used, for example, as a resonator. The multilayer microelectronic circuit comprises a plurality of dielectric layers and patterned electrodes which are laminated one upon another to form a laminated structure, the dielectric layers and the patterned electrodes forming an electrical circuit. The laminated structure has side surfaces extending along a direction in which the dielectric layers and the patterned electrodes are laminated. An input line is formed at one of the side surfaces and connected with an input section of the electrical circuit. An output line is formed at one of the side surfaces and connected with an output section of the electrical circuit. A grounding line is formed at one of the side surfaces and connected with a grounding section of the electrical circuit. Additionally, a signal line formed at one of the side surfaces, for connecting sections of the electrical circuit. The signal line has an end positioned adjacent a mounting surface at which the multilayer microelectronic circuit is directly mounted on the substrate, in which the end of the signal line is separate from the mounting surface so as to be insulated from electrical contact with the substrate.
摘要:
In order to produce resonance labels a coil having the shape of a spiral and a first capacitor surface located adjacent the innermost winding of the spiral and, furthermore, a supplementary surface adjacent the outer end of the spiral are produced at one side only of a supporting foil by an etching method from an aluminum foil arranged on the supporting foil. An aluminum foil strip is sealed onto the other side of the supporting foil at a superimposed position relative to the first capacitor surface, a few windings of the spiral and the supplementary surface to form the second capacitor surface. After establishing an electrical connection between this strip and the supplementary surface at the other side an electrical resonant circuit is produced. Due to the sealed on aluminum foil strip the etching procedure is reduced to only one side with the advantage that considerably less poisonous etching sludge is thus produced.
摘要:
A variable bandpass filter for filtering RF antenna signals to improve selectivity and reduce intermodulation distortion in an FM radio receiver includes a series resonant circuit which is modified to avoid blocking of AM signals. A bypass inductor is connected in parallel with the series resonant capacitor. The bypass inductor has a self-resonant frequency located between the AM and FM bands so that series resonant performance is maintained at FM frequencies and the bypassing function is exhibited at AM frequencies.
摘要:
The invention relates to a resonator structure comprising a printed board of an insulating material; a helix resonator mounted on the printed board, the helix resonator being formed by a wire wound into a cylindrical coil with a number of turns, one of the turns comprising a straight portion bent in parallel with the surface of the printed board; and a casing surrounding the helix resonator and having at least an inner and outer surface made of an electrically conductive material. In order to improve the reproduction fidelity of the matching of the helix resonator in series production, the resonator structure according to the invention is characterized in that a micro strip conductor is provided on the surface of the printed board, the microstrip being electrically connected to a predetermined position on said straight portion.
摘要:
The identification device in the form of a tag-like construction affixable to an object has at least one inductive element formed of flat conductor paths and a capacitive element formed from overlapping by overlaying conductor path parts and an interposed dielectric, which forms with the inductive element a closed resonant circuit, the conductor paths being arranged in at least two superimposed surfaces by folding together. In this way the conductor path parts forming the capacitive element are superimposed and they are at least partially identical with the conductor path parts forming the inductive element. In the method for the manufacture of the identification arrangement in the form of a tag-like construction affixable to an object, the conductor path constructions are arranged on an endless carrier path and the folding together of the conductor path construction is effected in that a continuously executed folding of the carrier path is carried out along a perforation line or fold-line.
摘要:
An electrical LC resonant circuit, particularly useful for channel filters in carrier frequency technology, has a fixed-tuned coil and a capacitor tunable by the removal of layer surface portions. The capacitor is constructed as an essentially flat, self-healing layer capacitor having a relatively small number of layer surfaces and dielectric layers lying one upon the other.