158 results about "Variable capacitor" patented technology

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.

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.

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.

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.

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.

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.

The present application provides a plasma processing device capable of controlling the position of a resonance point and bringing the resonance point close to the output end of a coil antenna. The device comprises an ICP antenna (21) having an input end (21I) and an output end (21O); a series circuit formed by connecting an additional inductor (24) and a variable capacitor (25) in series; and a control device (33) for changing the capacitance of the variable capacitor (25). The input end (21I) is connected to an antenna power source (23) via an antenna matching device (22), the output end (21O) is connected to the additional inductor (24), and the additional inductor (24) is connected to a ground end via the variable capacitor (25).

This invention discloses a sensor for detecting ice, water, and dryness states, comprising a substrate, a first metal line, a second metal line, a third metal line disposed on the surface of the substrate, a variable capacitor, an interdigitated capacitor, and a planar inductor. One end of the variable capacitor is connected to one end of the planar inductor via the first metal line, and the other end of the planar inductor is connected to one end of the interdigitated capacitor via the second metal line. The other end of the interdigitated capacitor is connected to the other end of the variable capacitor via the third metal line. The capacitance value of the interdigitated capacitor changes with the different dielectric constants of the materials between the interdigitated fingers. Since the relative dielectric constants of ice, water, and dryness change at different frequencies, the capacitance value of the interdigitated capacitor also changes. Therefore, this sensor for detecting ice, water, and dryness states has advantages such as simple structure, high recognition rate, small size, and process compatibility.

The application provides a controllable attenuator based on a complementary open resonant ring structure, which is composed of a cascaded active gain compensation amplifier and an open resonant low-pass filter. The open resonant low-pass filter comprises a microstrip low-pass filter, a complementary open resonant ring, a variable capacitor and a control circuit. The microstrip low-pass filter is composed of a middle dielectric layer and a first metal surface and a second metal surface located on both sides of the dielectric layer. The complementary open resonant ring is designed on the second metal surface. The variable capacitor is connected in parallel between the inner metal surface and the outer metal surface of the complementary open resonant ring. The capacitance of the variable capacitor is adjusted through the control circuit, so as to control the attenuation amplitude of the controllable attenuator based on the complementary open resonant ring structure. The controllable attenuator based on the complementary open resonant ring structure has a very small volume and can be integrated into a chip.

A method for operating a multi-channel variable capacitance capacitor device is disclosed, relating to the field of variable capacitor devices. The present invention comprises a circuit consisting of connection point X, connection point Y, and a second capacitor unit, wherein capacitor C... B1 To capacitor C B(n‑1) Capacitor C is connected to both ends. A1 To C An Connect the access point X and capacitor C. Ai A contactor S is provided between the contact point and the access point X. 1r Connection point Y, connection point Z, and the third capacitor unit form a circuit, and capacitor C C1 To capacitor C C(n‑1) Capacitor C is connected to both ends. D1 To C Dn Establish connection with access point Z, capacitor C Dl With the corresponding capacitor C Ck Contactors S are respectively installed between them. 2s Capacitor C B1 To capacitor C B(n‑1) Both ends are connected to contactor S 3t Connect capacitor C respectively C1 To capacitor C C(n‑1) Two ends. This invention obtains the desired capacitance value by adjusting the contactor combination, making the operation simpler and more flexible.

The present disclosure relates to voltage-controlled inverters. A voltage-controlled delay buffer includes a number of inverters configured in a cascade structure to receive an input signal from a source circuit and to output an output signal to an output circuit. The inverters include voltage-controlled inverters controlled by a control signal having a first voltage and a second voltage. The voltage-controlled inverters include a PMOS transistor to assist a low-to-high transition of the output signal and an NMOS transistor to assist a high-to-low transition of the output signal. Two variable capacitors, one connected in a forward direction and the other connected in a reverse direction, are used to adjust a delay of a transition of the input signal. Two other variable capacitors, one connected in a forward direction and the other connected in a reverse direction, are used to adjust a delay of a transition of the output signal according to the first voltage and the second voltage.

To provide a wireless charging system having a variable topology structure of a variable capacitor on a reception side.SOLUTION: An inverter is connected to an input end of a LCL-S type resonator compensation network, and an output end of the LCL-S type resonator compensation network is connected in cascade connection with a T-type resonance compensation network, can be placed in a constant current charging mode. The T-type resonance compensation network is connected to a commutator, and a capacitor CS2 branch circuit is added to the T-type resonance compensation network. A capacitor CSt is connected in parallel to a capacitor CS1 branch circuit of the T-type resonance compensation network, which becomes equivalent to one capacitor branch circuit of a F-type resonance compensation network. The capacitor CS2 is connected in series to a switch S1, the capacitor CSt is connected in series to a switch S2. The switches S1 and S2 are switched on simultaneously, so that the T-type resonance compensation network is converted into the F-type resonance compensation network and placed in the contant voltage charging mode.SELECTED DRAWING: Figure 1

A plasma generator may include a dielectric tube, an inner helical coil surrounding the dielectric tube and configured to generate plasma by forming a stationary wave of at least one of a magnetic field and an electromagnetic wave in the dielectric tube, a variable capacitor configuring a closed loop with the inner helical coil, an outer helical coil surrounding the inner helical coil and magnetically coupled to the inner helical coil, and a radio frequency (RF) power supply configured to provide RF power at a variable frequency to the inner helical coil.

This disclosure relates to a sensor and an electromagnetic pen, wherein the sensor includes a flexible circuit board, a variable capacitor, and a flexible conductor. The variable capacitor is disposed on the flexible circuit board and includes a first electrode and a second electrode. The flexible circuit board has a first side surface, and the first and second electrodes are located on the first side surface, with a capacitance between the first and second electrodes. The flexible conductor is disposed facing the first side surface. Under the action of a measured pressure, the flexible conductor contacts the first side surface and changes the contact area with the first side surface. The contact area is mapped to the capacitance value of the variable capacitor, which is used to characterize the pressure value of the measured pressure. Because the flexible conductor undergoes elastic deformation when it contacts the first side surface of the flexible circuit board under pressure, it absorbs the impact through deformation when the pen tip is dropped or impacted, thus preventing damage to the sensor.

A method and apparatus for processing a substrate are provided. For example, a matching network comprises a first sensor operably connected to the input of the matching network and an RF generator capable of operating at a first frequency, and a second sensor operably connected to the output of the matching network and a plasma processing chamber. The first and second sensors are configured to measure impedance during the pulse-on time of the RF generator. A variable capacitor is connected to the first and second sensors. A controller is configured to adjust at least one variable capacitor of the matching network during the pulse-on time of the RF generator based on an impedance value measured during at least one of the pulse-on or pulse-off states of a pulse voltage waveform generator connected to the matching network, or an RF signal from another RF generator capable of operating at a second frequency different from the first frequency.

To provide an atomic oscillator that can be miniaturized and manufactured on-chip while keeping costs down. [Solution] The atomic oscillator 10 detects the light transmitted through the gas cell 8 and the gas cell 8 containing alkali metal atoms to generate an electrical signal S LI A photodetector 9 converts the signal S to a high-frequency oscillator 31 using an FBAR. LI The input is a feedback signal S. FB A control circuit 1 outputs a feedback signal S FB The control circuit 1 further includes a laser light source 6 that outputs modulated light and introduces it into the gas cell 8, and a control circuit 1 further includes a variable capacitor 32 that adjusts the oscillation frequency of the high-frequency oscillator 31, and a high-frequency adjustment signal S tune The frequency converter 41 outputs the signal S output by the high-frequency oscillator 31. OUT The high-frequency adjustment signal S tune The system includes a frequency mixer 42 that mixes the gas with the gas and outputs a signal at a frequency that synchronizes with the resonant frequency of the gas cell 8.

An active feedback RF resonator has a signal loop having a signal input and a signal output. The signal loop has a variable gain stage and at least one variable resonator, each variable resonator comprising an inductance element and a variable capacitance element comprising a number of switched fixed value capacitors and a variable capacitor. A phase noise of the active feedback RF signal has a maximum value for an operating frequency of the variable resonator that is based on an operating range of the variable capacitor.

This invention relates to the field of variable capacitor technology, and in particular to a non-contact electrostatic detection device, comprising a carrier assembly including a circuit board; a sensing component disposed inside the carrier assembly; and a deformable component disposed above the carrier assembly. The carrier assembly further includes a shielding cover disposed above the circuit board and an opening slot on the shielding cover. A cavity is formed inside the shielding cover, and a sliding groove is formed at one end of the cavity. The sensing component includes a shielding plate disposed within the sliding groove, and a limiting protrusion is provided at one end of the shielding plate. The shielding plate and the limiting protrusion are L-shaped. This invention utilizes the Lorentz force generated by the components within the deformable component. This Lorentz force, in conjunction with the reciprocating vibration of the shielding electrode upon contact with an elastic element, avoids the mechanical wear associated with traditional motor solutions, thus extending the service life.

In one embodiment, an RF impedance matching circuit is disclosed. The matching circuit includes at least one electronically variable capacitor (EVC). Each EVC includes fixed capacitors, each of the fixed capacitors having a corresponding switching circuit for switching in and out the fixed capacitor to alter a total capacitance of the EVC. Each switching circuit includes a switch operably coupled to the fixed capacitor to cause the switching in and out of the fixed capacitor. The switch includes at least one string of series-connected PIN or NIP diodes. For each string, at least one of the diodes of the string has a balancing capacitor parallel to the diode.

A self-tuning apparatus and related methods include: a self-tuning device; a first voltage indicative of a first amplitude of an input signal to an antenna stored in a first capacitor when a variable capacitor bank coupled to the antenna is in a first configuration and a second voltage indicative of a second amplitude of the input signal when the variable capacitor bank is in a second configuration are compared. A first output signal based on the comparison is used to determine that the first configuration of the variable capacitor bank is an optimized configuration of the variable capacitor bank. The variable capacitor bank is configured in the first configuration.

The application 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 oscillation circuit comprises an upper resonant cavity composed of a basic oscillation circuit adopting a noise circulation structure and a lower resonant cavity composed of a noise suppression circuit adopting a Colpitts structure. The oscillation circuit adopts two groups of cross-coupled negative resistances of NMOS and PMOS, the former adopts a noise circulation structure of capacitive coupling, the latter adopts a Colpitts structure, and the two are connected through a tail inductor to improve the phase noise and power consumption of the circuit. The tuning circuit adopts a variable capacitor connected to the oscillation circuit and composed of a digital-controlled capacitor array and / or a self-tuning capacitor circuit; the capacitance value of the variable capacitor is adjusted to finely adjust the oscillation frequency. The application can solve the problem that the traditional noise circulation structure oscillator is difficult to comprehensively optimize the phase noise and power consumption.

The application relates to the technical field of radio frequency integrated circuits, and discloses a low-noise voltage-controlled oscillator circuit which comprises a source follower low-noise bias circuit with digital calibration, a cross-coupled amplifier array composed of multiple units, a stable DC bias switch capacitor unit array, a wide linear variable capacitor array driven by a ladder bias voltage, and an amplitude self-calibration loop composed of digital logic and a peak detector.