348 results about "Variable capacitor" patented technology

The present disclosure provides to a stretchable display device and a stretchable panel driving circuit, the display device including a stretchable display panel, a gate driving circuit configured to supply gate signals to pixels through gate lines, a data driving circuit, at least one stretch detection circuit group including at least one delay cell and at least one stretch variable capacitor disposed in a non-display area of the display panel, and configured to detect a delay time caused by stretch, a compensation control signal generator configured to generate a compensation control signal based on the delay time, and a timing controller configured to output a compensated signal based on the compensation control signal.

The invention provides a delay circuit applied to a time-interleaved analog-to-digital converter, the circuit comprises a first delay module, a second delay module and a delay selector, the first delay module is composed of multiple stages of delay units connected in series, each stage comprises a fixed inductor connected in series and a variable capacitor connected in parallel, and is used for providing large-range adjustable delay; the second delay module is connected to the output end of the first delay module and comprises a parallel combination of an adjustable constant current source and a programmable capacitor array, high-precision delay adjustment is achieved, the minimum adjustment step length of the second delay module is smaller than that of the first delay module, and multiple input ends of the delay selector are connected with output nodes of all stages of delay units respectively. The selection module is used for selecting coarse delay signals in different stages; the circuit realizes low-noise coarse delay adjustment through the inductance-capacitance network, completes high-precision fine delay adjustment by using current-capacitance combination, and has the advantages of wide delay range, high adjustment precision, low noise, good stability and the like.

The invention discloses an automatic impedance range calibration method for a radio frequency matcher, which comprises the following steps of: driving a variable capacitor of a standard matcher according with a design standard to scan and record impedance data under the connection mode that the input end is connected with a standard load and the output end is connected with a network analyzer and the specific configuration of the network analyzer; establishing a standard impedance range database; performing equivalent impedance scanning on the matcher to be calibrated in the same connection mode, and recording data; comparing the impedance data of the matcher to be calibrated with the standard database to determine an effective working interval of the capacitor; and finally, writing the effective interval as a limit into the control configuration of the matcher to be calibrated, and limiting the capacitance adjustment range of the matcher to be calibrated during normal operation. The automatic calibration system comprises a standard impedance measurement unit, an automatic control and data processing unit and a calibration execution unit. And the whole calibration process is controlled by a program, manual intervention is not needed, and the production efficiency is remarkably improved.

Embodiments of the present disclosure provide a system for fast impedance tuning. The system includes a radio frequency (RF) generator to generate power, a plasma chamber to receive the power from the RF generator and a RF matching network inserted between the RF generator and the plasma chamber configured to match a plasma load impedance to a RF generator impedance using a solid state based variable capacitor. The RF matching network includes a bias circuit that applies a reverse bias to the solid state based variable capacitor to control a capacitance value of the solid state based variable capacitor. The plasma load impedance is matched with the RF generator impedance when pulsed voltage, multi-level pulsing, or RF match ignition tuning is applied.

A plasma processing apparatus includes a vacuum container and a plasma source that generates plasma in the vacuum container. The plasma source includes an antenna, an RF power supply connected to one end of the antenna and configured to supply an RF power to the antenna, and a variable capacitor connected to the other end of the antenna and having a variable capacitance.

An oscillator circuit, a corresponding radar sensor, a vehicle, and an operating method are disclosed. An oscillator includes a tunable resonant circuit having an inductor and a variable capacitor coupled between a first node and a second node, and a set of capacitors selectively coupled between the first node and the second node. An input control node receiving an input control signal is coupled to the variable capacitor and the set of capacitors. The tunable resonant circuit is tunable based on the input control signal. A biasing circuit biases the tunable resonant circuit to generate a variable frequency output signal between the first node and the second node. A voltage divider generates a set of different voltage thresholds, and a set of comparator circuits having hysteresis compares the input control signal with the set of different voltage thresholds to generate a set of control signals. The capacitors in the set of capacitors are selectively coupled between the first node and the second node according to the control signals in the set of control signals.

The invention relates to the technical field of radio frequency integrated circuits, and discloses a low-noise voltage-controlled oscillator circuit which comprises a source electrode following low-noise bias circuit with digital calibration, a source electrode following low-noise bias circuit with digital calibration, a source electrode following low-noise bias circuit with digital calibration and a source electrode following low-noise bias circuit with digital calibration, the cross-coupled amplifier array is composed of a plurality of units, and the source electrode of the cross-coupled amplifier array suppresses low-frequency noise through a resistance-capacitance feedback network and receives a digital amplitude calibration signal so as to dynamically adjust the number of working units and stabilize the output amplitude; the amplitude self-calibration loop consists of digital logic and a peak detector; the switched capacitor unit array is provided with stable direct-current bias; and a wide linear variable capacitor array driven by the stepped bias voltage. Through deep fusion of digital and analog technologies, the phase noise is remarkably reduced, the linear tuning range is widened, the amplitude stability is ensured, the power consumption is reduced, and the method is particularly suitable for a high-performance radio frequency communication chip of the Internet of Things.

A plasma processing apparatus includes a chamber, a bias power supply to supply a pulsed bias DC signal, a substrate support to support a substrate and an edge ring in the chamber, and an electrical path. The substrate support has an electrostatic chuck that includes a first region to hold the substrate and a second region provided around the first region and to hold the edge ring, and is formed from a dielectric, a first bias electrode inside the first region, a second bias electrode inside the second region, a base to support the electrostatic chuck, and a first impedance adjustment mechanism to have a first variable capacitor connected between the second bias electrode and the base.

The invention relates to the technical field of radio frequency integrated circuits, and discloses a dynamic bias C-type voltage-controlled oscillator based on a CMOS (complementary metal oxide semiconductor) process, the voltage-controlled oscillator adopts a C-type structure, a cross-coupled network adds two resistors and a capacitor on the basis of a cross-coupled transistor, a circuit works in the C type by adjusting bias voltage at a resistor end, and the voltage-controlled oscillator works in the C type. The C-type voltage-controlled oscillator, a tail current source, a variable capacitance network, a switched capacitor array and a fixed LC resonance network form a core structure of the C-type voltage-controlled oscillator capable of numerical control tuning and voltage-controlled tuning, so as to determine the working frequency of the circuit and realize numerical control and voltage-controlled tuning functions; and the operational amplifiers with two bandwidth modes are introduced, so that the problem of difficult oscillation starting is solved, and the oscillation starting speed and the phase noise performance in a stable state are considered at the same time.

The invention discloses an impedance matching method and system for chip testing, electronic equipment and a medium, and relates to the technical field of data processing. The method comprises the following steps: establishing electrical connection between a test probe and a to-be-tested chip test point, and sending a preset detection signal; acquiring incident power and reflection power of the detection signal; calculating a first signal reflection coefficient based on the incident power and the reflection power, and determining an impedance deviation value and an adjustment direction according to a difference value between the first signal reflection coefficient and a preset standard reflection coefficient; determining a parameter adjustment step length according to the impedance deviation value; sequentially adjusting a variable resistor, a variable capacitor and a variable inductor in the impedance matching network according to the step length and the adjusting direction; detecting a second signal reflection coefficient when the impedance real part and imaginary part of the variable element reach the target range; and judging whether the second signal reflection coefficient converges to a preset range, and if yes, taking the current matching network parameter as an impedance matching result. By implementing the technical scheme provided by the invention, the impedance matching accuracy of the chip test can be improved.

In one embodiment, an RF impedance matching circuit is disclosed. The matching circuit is coupled between a plasma chamber and an RF source. The matching circuit includes a first electronically variable capacitor (EVC) having a first variable capacitance, a terminal of the first EVC being operably coupled to the RF input, and a second EVC having a second variable capacitance, a terminal of the second EVC being operably coupled to the RF output. A control circuit determines, based on a first parameter, a first capacitance value for the first EVC and a second capacitance value for the second EVC. The control circuit then generates a control signal to alter the first and second variable capacitances accordingly. The alteration of the capacitances, while the frequency of the RF source is not altered, causes RF power reflected back to the RF source to decrease.

The invention relates to the field of integrated circuits, in particular to a multi-injection locking annular traveling wave oscillator, a Doppler radar based on the annular traveling wave oscillator and physiological feature detection equipment based on the annular traveling wave oscillator. Comprising 16 inductive elements. Four variable capacitors and four mirror image injection circuits. The inductive elements are sequentially connected end to end. And every two adjacent inductive elements form a phase shift channel and are sequentially distributed in four orthogonal directions. And the two phase shift channels in each direction are parallel to each other and are positioned on the inner side and the outer side of the same layer of the layout. The phase shift channels on the inner and outer sides in adjacent directions are alternately connected, and the wires between the phase shift channels are distributed on the upper and lower layers in the layout at equal intervals. The mirror image injection circuit and the variable capacitor are connected between the two phase shift channels in each direction and output injection signals with the phase difference of 180 degrees to the phase shift channels. According to the invention, the problems of limited injection locking range, high noise and insufficient phase uniformity of the existing oscillator for the Doppler radar are solved.

In a microelectromechanical system (MEMS) sensor, movement of a component such as a proof mass due to a force of interest is sensed capacitively. A capacitance-to-voltage (C2V) converter receives a capacitance signal from the sensor and outputs a signal that includes an offset in addition to a signal of interest. The output signal is analyzed to identify the offset portion of the output signal and to modify values one or more variable capacitors coupled to the C2V input reduce the offset portion of the output signal.

A controller and a method is provided for controlling a capacitance of an LC circuit having a circuit frequency including, a variable capacitor to couple with an external inductor as part of an LC circuit, a target value, a spread spectrum function to generate an adjustment value, and a circuit to poll the target value, call the spread spectrum function, and set a capacitance of the variable capacitor based on the sum of the target value and the adjustment value.

A method for molding and processing a variable capacitor, the method comprising the following steps: feeding a molten material into a molding apparatus, molding a housing of a capacitor by means of the molding apparatus, and removing the molded housing from the molding apparatus; mounting a semiconductor substrate inside the molded housing, forming a first well of a first conductivity type in a first region of the semiconductor substrate, and then forming a second well of a second conductivity type in a second region adjacent to the first region of the semiconductor substrate; and forming a first insulating film above the first region and the second region of the semiconductor substrate, and forming a gate electrode above the first insulating film of the first region, wherein the molding apparatus comprises a fixing base. By using the method for molding and processing a variable capacitor, a workpiece can be conveniently molded in one step, the processing operation is simple, continuous processing can be achieved, and the processing efficiency is high.

In one embodiment, a variable capacitor includes a first elongate member including a first conductive portion disposed toward a first distal end of the first elongate member and a second conductive portion disposed toward a second distal end of the first elongate member, the first elongate member is configured to pivot on a first fulcrum disposed between the first conductive portion and the second conductive portion, a first distance between the first fulcrum and a first conductive portion of the first elongate member is different from a second distance between the first fulcrum and a second conductive portion of the first elongate member; a second elongate member including a first conductive portion disposed toward a first distal end of the second elongate member and a second conductive portion disposed toward a second distal end of the second elongate member, where: one of the first elongate member and the second elongate member is a cathode; one of the first elongated member and the second elongated member is a cathode, and the other of the first elongated member and the second elongated member is an anode, the cathode and a respective first conductive portion of the anode forming a first capacitor, where a capacitance of the first capacitor is a function of a first pivot angle of the first elongated member on a first fulcrum, the capacitance of the second capacitor is a function of a first pivot angle of the first elongate member on the first fulcrum, the first conductive portion of the cathode and the second conductive portion of the anode are connected to a positive voltage of the first circuit, and the second conductive portion of the cathode and the second conductive portion of the anode are connected to a negative voltage of the second circuit. The first conductive portion and the second conductive portion of the anode are connected to a negative voltage of the first circuit such that the first capacitor and the second capacitor are connected in parallel. And wherein: the application of the potential difference by the first circuit results in pivoting of the first elongate member, a corresponding change in capacitance of the first capacitor proportional to the potential difference, and a corresponding change in capacitance of the second capacitor inversely proportional to the potential difference, and wherein the amplitudes of the capacitance changes of the first capacitor and the second capacitor are different, the sum of the capacitance of the first capacitor and the second capacitor varies with the potential difference.

A rectifier circuit (10) for a passive RFID circuit (1), including: a first rectifier stage (11) having a positive stage input (14) connectable to a first antenna port (6) and a negative stage input (15) connectable to a second antenna port (7); a first rectifying unit (12) connected to the positive stage input (14) and to a positive stage output (16); a second rectifying unit (18) connected to the negative stage input (15) and to a negative stage output (17); and a trimming capacitor (30) connected to the positive stage input (14) and to the negative stage input (15). The trimming capacitor (30) is electronically switchable to a first capacitance and to a second capacitance, and a voltage dependent variable capacitor (50) is connected to the positive stage input (14) and to the negative stage input (15).

In one aspect, the present invention concerns a rectifier circuit (10) for a passive RFID circuit (1), the rectifier circuit (10) comprising: - at least a first rectifier stage (11) comprising a positive stage input (14) connectable to a first antenna port (6) and comprising a negative stage input (15) connectable to a second antenna port (7), - a first rectifying unit (12) connected to the positive stage input (14) and connected to a positive stage output (16), - a second rectifying unit (18) connected to the negative stage input (15) and connected to a negative stage output (17), - a trimming capacitor arrangement (30) connected to the positive stage input (14) and connected to the negative stage input (15), wherein the trimming capacitor arrangement (30) is electronically switchable to at least a first capacitance and to a second capacitance, and - a voltage dependent variable capacitor arrangement (50) connected to the positive stage input (14) and connected to the negative stage input (15).

The utility model discloses a plasma type variable capacitor, and relates to the technical field of electrical elements. The utility model aims to solve the problems that the capacitance value of the conventional variable capacitor is at an nF level or smaller, the volume is large and the conventional variable capacitor is easy to wear. The right side end face of a first conductive electrode is tightly connected with the left side end face of a first dielectric medium, the left side end face of a second conductive electrode is tightly connected with the right side end face of a second dielectric medium, a gap is formed between the right side end face of the first dielectric medium and the left side end face of the second dielectric medium, and gas is arranged in the gap. A first exciting electrode and a second exciting electrode are arranged between the inner side edge and the outer side edge or the outer side edge of the gap, and when a power supply is externally connected between the first exciting electrode and the second exciting electrode, gas in the gap can be ionized into conductive plasma. According to the utility model, the dielectric barium titanate with high dielectric constant can be used, the capacitance value is ultra-large and reaches uF level or higher, the capacitance value can be adjusted according to the voltage of an external power supply, and the relative volume is small.

A flexible variable capacitor and its fabrication method are disclosed. The flexible variable capacitor comprises two highly conductive flexible electrode layers and an elastomeric dielectric insulating layer located between the two highly conductive flexible electrode layers. The highly conductive flexible electrode layers contain a first polymer elastomer and carbon nanomaterials, and the elastomeric dielectric insulating layer contains a second polymer elastomer and functional ceramic nanoparticles. The fabrication method of the flexible variable capacitor is as follows: first, an elastomeric composite film with different functions is prepared; then, the upper and lower electrode layers are pressed together with the intermediate elastomeric insulating layer to obtain a stretchable strip-shaped planar capacitor. Unlike existing technologies, this application uses independently developed highly conductive flexible electrodes to replace traditional silver-oil electrodes, significantly reducing the cost of the variable capacitor device and improving its integration and operability. The fabricated flexible variable capacitor features high dielectric constant, low dielectric loss, simple fabrication process, and sensitivity to deformation.

Embodiments of the present disclosure provide a system for fast impedance tuning. The system includes a radio frequency (RF) generator to generate power, a plasma chamber to receive the power from the RF generator and a RF matching network inserted between the RF generator and the plasma chamber configured to match a plasma load impedance to a RF generator impedance using a solid state based variable capacitor. The RF matching network includes a bias circuit that applies a reverse bias to the solid state based variable capacitor to control a capacitance value of the solid state based variable capacitor. The plasma load impedance is matched with the RF generator impedance when pulsed voltage, multi-level pulsing, or RF match ignition tuning is applied.

The application discloses a kind of plasma reactor and the method for power compensation to focus ring, and plasma reactor includes: reaction cavity, substrate support unit, is arranged at the inside bottom of reaction cavity;Substrate support unit includes: pedestal, which is connected to the radio frequency power supply device located outside the reaction cavity by matching circuit;Electrostatic chuck is arranged on the pedestal;The upper surface of electrostatic chuck is used to adsorb substrate;Focus ring, focus ring surrounds electrostatic chuck;Power regulating device is respectively connected with focus ring and matching circuit radio frequency coupling;Power regulating device includes: series inductance and variable capacitor, for adjusting the impedance of branch where focus ring is located, to adjust the radio frequency power coupled on focus ring, prolong the service life of focus ring, prolong maintenance period.

This invention provides an automatic tuner for a loop antenna used in shortwave communication, belonging to the field of shortwave communication technology. This tuner aims to solve the problems of existing automatic tuners for loop antennas, such as difficulty in balancing versatility and high power performance, and poor high-voltage withstand capability. The tuner includes: a matching circuit, which includes couplers for shunting forward and reverse radio frequency signals; a tuning actuator, which includes an oil-immersed variable capacitor and a drive mechanism; and a main control circuit. Based on the signal shunted by the coupler, the main control circuit autonomously calculates the standing wave ratio (VSWR) and generates a control signal to control the matching circuit and tuning actuator independently of the radio transceiver, thus completing automatic tuning. This invention improves voltage withstand and power handling capability by using an oil-immersed variable capacitor, and achieves universal tuning through the autonomous control of the main control circuit, overcoming the shortcomings of existing technologies and offering the advantages of high power, high reliability, and strong versatility.

Embodiments of the present disclosure generally relate to methods and apparatus for measuring and controlling local impedance at a substrate support in a plasma processing chamber during substrate processing. The substrate support includes a plurality of substrate support pins, in which a radio frequency voltage, a current, and a phase of each of the plurality of substrate support pins are measured, and an impedance of the support pins is adjusted in real time. Each of the substrate support pins is coupled to an associated, remotely controllable, adjustable impedance circuit. In one embodiment, a variable capacitor is used to adjust the impedance of an impedance circuit coupled to an associated substrate support pin, and may be remotely adjusted with a stepping motor. In another embodiment, a microcontroller may control impedance adjustment of all of the plurality of substrate support pins, and may be used to track the impedances to each other and track the impedances with a body impedance of the plasma processing chamber.

The invention relates to the field of integrated circuits, in particular to a K-band voltage-controlled oscillator based on a noise circulation structure, a phase-locked loop and a chip. The voltage-controlled oscillator comprises an oscillation circuit and a tuning circuit. The oscillating circuit comprises an upper resonant cavity formed by a basic oscillating circuit adopting a noise circulation structure and a lower resonant cavity formed by a noise suppression circuit adopting a Colpitts structure. The oscillating circuit adopts two groups of cross-coupled negative resistors, namely NMOS and PMOS, the cross-coupled negative resistors adopt a capacitance-coupled noise circulation structure, the PMOS adopts a Colpitts structure, and the cross-coupled negative resistors are connected through a tail inductor so as to improve phase noise and power consumption of the circuit. The tuning circuit adopts a variable capacitor which is connected to the oscillation circuit and is composed of a numerical control capacitor array and / or a self-adjusting capacitor circuit; and the capacitance value of the variable capacitor is adjusted to realize fine adjustment of the oscillation frequency. According to the invention, the problem that a traditional oscillator with a noise circulation structure is difficult to realize comprehensive optimization of phase noise and power consumption can be solved.

This invention discloses a radio frequency (RF) power control system and method, and an RF plasma system. The method includes: before the electrostatic chuck cleaning begins, loading a preset parameter set of an impedance matching network associated with the selected cleaning process recipe, and driving the variable capacitors and variable inductors in the impedance matching network to their preset initial positions in the preset parameter set before applying continuous wave RF power; applying continuous wave RF power to the electrostatic chuck and initiating the cleaning process; during the cleaning process, acquiring the load impedance in the impedance matching network in real time at a preset sampling rate, generating a real-time impedance trajectory, and calculating the impedance change rate; determining the current cleaning stage of the electrostatic chuck based on the magnitude of the load impedance and the impedance change rate, and dynamically switching to the impedance matching algorithm corresponding to the cleaning stage to adjust the positions of the variable capacitors and variable inductors in the impedance matching network. This invention achieves low-reflection power matching throughout the entire cleaning process.

The invention relates to a W-band low-noise voltage-controlled oscillator based on a transformer resonant cavity and harmonic extraction. The W-band low-noise voltage-controlled oscillator comprises a dual-core in-phase coupled oscillator core, a two-bit switched capacitor bank, a linear variable capacitor bank and an output buffer, the dual-core in-phase coupled oscillator core comprises a transformer resonant cavity and a harmonic extraction network, a fundamental wave oscillation signal is generated in the transformer resonant cavity and is coupled and output to the output buffer, and a high-power second harmonic oscillation signal is generated in the harmonic extraction network and is output as a target oscillation signal; the two-bit switched capacitor bank adopts an HBT switch with excellent high-frequency performance, the tuning range of the oscillator is divided into four sub-bands, and the tuning gain is reduced; the capacitance value of the linearized variable capacitor bank is linearly changed along with the tuning voltage height, and a conversion mechanism of flicker noise is inhibited; and the output buffer realizes load isolation and buffering of the fundamental wave oscillation signal. The voltage-controlled oscillator has low tuning gain and high output power in the W wave band, and excellent phase noise is achieved.

MEMS converter (200, 300, 400) for integration into a microphone arrangement (100) having a housing in which the MEMS converter is arranged, the MEMS converter comprising: a substrate (202) comprising an aperture (212); an electroacoustic transduction element (204) coupled to the substrate (202), the transduction element (204) comprising a fixed electrode (210) and a movable electrode (208) located on different layers of the MEMS transducer to form a variable capacitor, and the movable electrode (208) being at least partially disposed over the aperture (212); electrical contacts (414a, 414b) coupled to the transduction element (204); a resistor (206, 306); and electrical contacts (416) coupled to the resistor (206, 306) and electrically insulated from the electrical contacts (414a, 414b) of the transduction element (204), wherein the transduction element (204) comprises an insulating material (214) connected to the substrate, wherein the resistor (206, 306) is arranged laterally offset from the aperture (212) of the substrate (202, 502) and the insulating material (214) forms a backplate structural layer (508, 516), in the surface of which facing the substrate (202) the fixed electrode (210) is sunk, wherein the resistor (306) is sunk into said surface and is arranged in the same layer as the fixed electrode (210) and is formed of the same material, or wherein the resistor (206) is suspended from said surface and is arranged in the same layer as the movable electrode (208) and is formed of the same material.

Disclosed are a micro-electromechanical system (MEMS) structure and an MEMS microphone comprising same. The MEMS structure comprises a back plate; and a diaphragm located on one side of the back plate, wherein the diaphragm and the back plate forms a variable capacitor, the diaphragm comprises multiple first through holes and air release structures respectively corresponding to the first through holes, and the diaphragm further comprises one or more second through holes penetrating through the diaphragm.

The invention relates to the technical field of variable capacitors, and discloses a grid-controlled semiconductor depletion layer modulation vacuum variable capacitor and a preparation method thereof, and the capacitor comprises an upper electrode which is made of high-purity oxygen-free copper and has a rounding edge structure; the lower electrode is made of oxygen-free copper and also serves as a mechanical support and a heat sink; the vacuum insulating layer is arranged between the upper electrode and the lower electrode; the semiconductor layer is N-type monocrystalline silicon, the thickness of the semiconductor layer is 200 micrometers, the resistivity of the semiconductor layer is 4-6, and impurity concentration of the semiconductor layer is 4-6. According to the invention, the high-voltage-withstanding vacuum gap capacitor and the semiconductor depletion layer capacitor based on MOS gate voltage regulation and control are connected in series and integrated, so that the single device has high-voltage insulation and rapid electric regulation capabilities at the same time creatively; the capacitance value can be continuously and accurately adjusted in the order of tens of nanoseconds to microseconds only by applying a small-amplitude low-voltage signal.