1378 results about "Signal generator" patented technology

The invention provides a tumor electric field treatment system, an electrode slice temperature detection method and an electrode slice anomaly detection method, the system comprises an alternating current signal generator, an electrode slice and a controller, the electrode slice comprises a plurality of electrode units and a plurality of temperature detection units, the plurality of temperature detection units are divided into a plurality of row groups and a plurality of column groups, and the plurality of electrode units are connected with the controller. The grounding ends of the temperature detection units in each row group are jointly connected to the same grounding wire, and the signal ends of the temperature detection units in each column group are connected to the same dual-purpose signal wire after being in short circuit with the corresponding electrode units; when the dual-purpose signal line is connected to the temperature sampling point, the grounding wires are sequentially conducted, so that temperature detection signals detected by the temperature detection units are sampled based on the temperature sampling point; when the dual-purpose signal line is connected to the alternating power line, alternating electric signals are transmitted to the electrode units. Therefore, the temperature of the electrode plate can be detected by using fewer conductive traces, and whether the electrode plate is abnormal or not can be judged through temperature detection.

The invention relates to an SOC chip performance test device, method and equipment and a readable storage medium. In the device, an upper computer is used for sending an excitation instruction to a voltage simulator and sending a test instruction to a signal generator according to a test requirement; the voltage simulator is used for inputting a voltage excitation signal to the test board according to the excitation instruction; the signal generator is used for inputting a test signal to the test board according to the test instruction; the test board is used for conditioning the voltage excitation signal and the test signal and sending a first conditioning signal to the SOC chip to be tested so as to indicate the SOC chip to be tested to respond to the first conditioning signal; the test board is also used for acquiring a response signal returned by the SOC chip to be tested, conditioning the response signal, and returning a second conditioning signal to the upper computer; and the upper computer is also used for analyzing the second conditioning signal to obtain a performance test result. The SOC chip performance test efficiency can be improved.

The invention discloses a multi-modal interaction evaluation system and method based on synchronous data acquisition, and relates to the technical field of biomedical engineering and man-machine interaction, and the method comprises the steps: generating a synchronous pulse sequence through a synchronous signal generator according to the same coding time base, and outputting the synchronous pulse sequence to an optical path and an electrical path at the same time; pulse events are recognized in the video and the electrophysiological data respectively, and observation pairs of counting numbers and timestamps are obtained; time drift is continuously estimated and compensated through robust regression in a sliding window, and a unified time axis is generated; furthermore, a dynamic time window of heart beat anchoring is constructed according to an R peak event of the electrocardiosignal, and consistent segmentation and feature extraction of cross-modal data are achieved.

The invention provides an underground pipe column detection method and system and a medium, and the underground pipe column detection system comprises detection equipment, an excitation signal generator and an underground detection device; the detection equipment is in communication connection with the excitation signal generator and the underground detection device; the underground detection device comprises a transmitting coil and a magnetic sensor array consisting of a plurality of receiving coils; the excitation signal generator is configured to apply transient excitation current to the transmitting coil; the transient excitation current enables the transmitting coil to generate an excitation magnetic field; the excitation magnetic field enables the sleeve layer to generate an induced magnetic field; the magnetic sensor array is configured to collect the magnetic field intensity of the induced magnetic field and generate a magnetic field intensity vector; the detection equipment is configured to perform sparse reconstruction solution on the target vector containing the wall thickness information of the casing layer according to the magnetic field intensity vector and the space observation matrix corresponding to the magnetic sensor array, and through the embodiment of the invention, the limitation of the number of array elements on the detection resolution can be broken through, and the detection precision of the wall thickness of the underground pipe column is improved.

The invention relates to a high-voltage transformer series resonance withstand voltage test system and an automatic tuning method, and relates to the technical field of high-voltage electrical equipment testing, and the system comprises a control module, a signal generator, a resonance circuit, a data acquisition module and a safety protection unit. The method comprises the following steps: initializing system parameters; automatically searching and locking an optimal resonant frequency point; executing a withstand voltage test at the resonance point and monitoring data; and automatically analyzing data and judging performance. According to the invention, through full-closed-loop automatic control, rapid and accurate locking of the resonant frequency and intellectualization of the test process are realized, and the problems of low efficiency, poor precision and insufficient safety of a traditional method are effectively solved. The device has the outstanding advantages of high adaptive capacity, reliable test result and safety and convenience in operation, and is particularly suitable for high-efficiency and accurate standardized test on the insulating properties of various high-voltage transformers in an electric power system.

A radar system injects a calibrated current at a signal generator during a reset portion and acquisition portion of each chirp period. The signal generator employs “gear-switching” to reduce PLL bandwidth during an acquisition phase and to increase the phase lock loop (PLL) bandwidth during a reset phase. By employing gear switching to change the bandwidth of the PLL circuit during the different portions of each chirp period, the length of the reset period is reduced, thus improving overall efficiency of the radar system while maintaining good performance.

A device and method for representing the foam porosity state of foamed lightweight soil with self-adjusting beams, and relates to the technical field of sound absorption coefficients measurement; the device includes a standing wave tube, a plurality of polyvinylidene fluoride piezoelectric films, a sensor, an exciter, a push-pull handle, an adjustable telescopic tube, a foamed lightweight soil detection material, a charge amplifier, a data memory, a data adapter, a signal generator, an adaptive power amplifier board, and a PC computer; the device of the invention has low cost, long service life, high measurement accuracy, relatively simple production process, and can be applied to different scenarios.

The invention discloses a weak magnetic field synchronous measurement device and a weak magnetic field synchronous measurement system, and the device comprises a signal generator which is used for outputting a first AC constant current power supply and a second AC constant current power supply; the reference magnetic field generation device is electrically connected with the signal generator, and the reference magnetic field generation device is used for being connected with a direct-current constant-current power supply and a first alternating-current constant-current power supply to generate a reference magnetic field; the magnetic field detection device is electrically connected with the signal generator, and the magnetic field detection device is used for being driven by a second alternating-current constant-current power supply, detecting a reference magnetic field and outputting a reference magnetic field detection signal; and the signal demodulating device is electrically connected with the magnetic field detection device, the signal demodulating device is used for demodulating the reference magnetic field detection signal to obtain a reference signal and outputting the amplitude and phase of the reference signal on a first reference frequency and a second reference frequency, and the second reference frequency is twice of the first reference frequency. According to the invention, a complex magnetic field formed by superposing a steady magnetic field and an alternating magnetic field can be measured.

The utility model discloses an electromagnetic compatibility assessment device, and belongs to the technical field of wireless communication. The equipment comprises a data processing module, a signal generator module, a low-frequency / high-frequency amplifier, a combining unit, a shielding frame and a power supply module, and accurate evaluation of the electromagnetic compatibility of the weak current equipment is realized through modular design. The signal generator module adopts a multi-band vector signal generator to generate configurable interference signals; the low-frequency amplifier and the high-frequency amplifier respectively adopt independent high-precision amplification circuits; and the combining unit couples the two paths of signals into a composite interference signal and outputs the composite interference signal. The shielding frame is made of double-layer aluminum magnesium alloy and is combined with a metal machine frame to form a composite shielding system. And the data processing module regulates and controls parameters in real time through the touch screen, analyzes response data of the tested equipment based on an FFT algorithm, and generates a visual evaluation report.

The invention discloses a dynamic test method and system for tissue frequency domain impedance characteristics, and belongs to the technical field of medical detection. The system comprises an energy generator, a bipolar scalpel, a signal generator, a radio frequency power amplifier module, a control unit, two loop switches, a sampling probe and a test unit. An electrode of the bipolar scalpel is used for being in contact with a biological tissue to be subjected to frequency domain impedance characteristic testing; the energy generator is connected with the first loop switch and is used for outputting an electric resection / electrocoagulation signal to the biological tissue so as to dynamically reproduce the state change of the biological tissue; and the signal generator inputs a broadband excitation voltage signal to the biological tissue through the radio frequency power amplifier module and the second loop switch. The control unit is used for coordinating on-off of the two loop switches. The sampling probe is used for collecting voltage and current signals of the double electrodes in real time and feeding back the signals to the testing unit. The test unit generates a real-time impedance characteristic spectrogram of the biological tissue along with frequency change. The tissue impedance change can be monitored on line in real time.

The invention discloses a beat frequency comparison device mediated by an optical frequency comb. The beat frequency comparison device comprises the optical frequency comb, a first frequency stabilized laser, a first beat frequency device, a first frequency mixer, a first high-pass filter, a second frequency stabilized laser, a second beat frequency device, a second frequency mixer, a second high-pass filter, a DDS signal generator, a third frequency mixer and a low-pass filter. Frequency-stabilized lasers output by the first frequency-stabilized laser and the second frequency-stabilized laser and an optical frequency comb output by the optical frequency comb are subjected to beat frequency in the first beat frequency device and the second beat frequency device respectively, and first beat frequency and second beat frequency are obtained; the first beat frequency and the second beat frequency are mixed with the carrier envelope offset frequency of the optical frequency comb, and a first sum frequency and a second sum frequency are filtered out; the first sum frequency obtains a synthetic frequency through direct digital frequency synthesis; the second sum frequency and the synthetic frequency are mixed in the third mixer, and then the difference frequency is filtered out through the low-pass filter. According to the invention, beat frequency comparison of frequency-stabilized lasers with different wavelengths can be realized, and the influence of the stability of the optical frequency comb is avoided.

The invention relates to a Rydberg atomic communication receiving system and method based on AT split peak value analysis, and belongs to the technical field of quantum communication. The system comprises a detection laser, a coupling laser, an AOM / EOM, a function generator, a high-frequency signal generator, a cesium atom gas chamber, a photoelectric detector, a lock-in amplifier, a data acquisition module and a microwave signal output module. The AOM / EOM modulates the frequency of the detection laser; the microwave signal output module generates an AM modulation microwave signal and transmits the AM modulation microwave signal to the cesium atom gas chamber, so that the target Rydberg state atoms generate an AT splitting effect to calibrate system parameters; the photoelectric detector and the lock-in amplifier obtain a first harmonic component based on the transmission light. During communication, the system is arranged in a microwave electric field received by communication, and the data acquisition and processing module outputs AM modulation microwave signals received by the recovered cesium atom gas chamber based on calibrated system parameters and phase locking. The method solves the problem of signal distortion existing in EIT-AT direct communication transmission and the problem of tedious operation of a heterodyne method.

An integrated circuit device includes: one or more switches of a Buck converter; and a control circuit for the Buck converter including: a comparator configured to generate a comparator output signal by comparing a feedback voltage of the Buck converter with a compensation ramp voltage; a pulse generator configured to generate, in response to a rising edge in the comparator output signal, a pulse signal for controlling the Buck converter; a transconductance amplifier configured to generate, at an output terminal of the transconductance amplifier, a current proportional to a difference between a reference voltage and the feedback voltage; a capacitor coupled between the output terminal of the transconductance amplifier and a reference voltage node; and a ramp signal generator configured to generate the compensation ramp voltage by adding a voltage at the output terminal of the transconductance amplifier and a ramp voltage generated by the ramp signal generator.

The invention provides a DC-DC forward boost-buck power conversion circuit based on cascaded Cuk topologies, and relates to the technical field of power electronic conversion, the circuit is mainly formed by cascading two Cuk topologies sharing one inductor, and the circuit also comprises a power supply end, a load end and a same-frequency driving signal generator. The same-frequency driving signal generator controls the two power switch tubes in the Cuk topology through a same-frequency signal, and the output voltage is adjusted by adjusting the duty ratio. The circuit not only keeps the advantage of continuous input and output current of a traditional Cuk circuit, but also converts the polarity of the output voltage from the reverse direction to the forward direction, and meanwhile, the voltage gain is remarkably improved, so that forward voltage conversion can be efficiently and smoothly realized. The circuit structure has the characteristics of high gain, forward output, continuous current, simple control and the like, and is suitable for occasions requiring high-efficiency and high-quality electric energy conversion, such as new energy power generation and energy storage, electric automobiles, precision industry and the like.

The invention belongs to the technical field of photoelectric fusion integrated circuits, and particularly discloses a parallel PWM expansion high-precision programmable DAC structure. The adjusting module is used for adjusting the thermo-optical phase shifter according to the received digital control signal; the DAC structure specifically comprises a pulse width modulation signal generator and a current source array, wherein the pulse width modulation signal generator is used for acquiring a low-order code element from the digital control signal to generate a pulse width modulation signal, and sending the pulse width modulation signal to the current source array; wherein the current source array is used for acquiring a high-order code element from the digital control signal to generate a high-order analog signal; a low-order analog signal is generated based on the pulse width modulation signal; and the processor is also used for weighting and accumulating the low-order analog signal and the high-order analog signal to obtain an analog control signal and outputting the analog control signal. The DAC structure is high in precision and simple in structure.

The invention provides an automatic test system and method for a third-party high-power repeater, and relates to the technical field of automatic test equipment, and the system comprises an integrated reconfigurable passive link box, a control host, a vector signal generator and a vector signal analyzer. The integrated reconfigurable passive link box comprises a box body, a radio frequency switch matrix network, an embedded function network, a control port, an input port, an output port, an uplink interface and a downlink interface. The radio frequency switch matrix network and the embedded function network are arranged in the box body. The input port, the output port, the uplink interface and the downlink interface are arranged on the surface of the box body. The vector signal generator is connected with the input port, the vector signal analyzer is connected with the output port, and a third-party high-power repeater to be tested is arranged between the uplink interface and the downlink interface. According to the invention, the radio frequency switch matrix network and the embedded function network are packaged in the integrated reconfigurable passive link box, and the control host is utilized to carry out automatic testing on the third-party high-power repeater according to the preset process, so that frequent operation processes are avoided, and damage to instruments is reduced.

A fault detection system for detecting a fault condition in a direct current (DC) system. The system may include a DC power transmitter to energize a cable and a DC power receiver connected to the cable. A signal generator at the receiver employs orthogonal frequency division multiplexing (OFDM) and combines symbols for messaging or data communications with redundant symbols dedicated to fault detection. At a signal receiver, the transmitted OFDM signal is used to measure changes in the channel transfer function by monitoring changes in a parameter of the received redundant symbols. The redundant symbols need not be decoded to detect a greater-than-threshold change in the transfer function that is indicative of a fault on the cable.

The invention discloses a deviation correction method and system for load prediction during severe weather. The method comprises the following steps: acquiring historical load data and weather prediction information; generating a baseline load prediction value through a baseline prediction model based on historical data; judging whether a major weather event is triggered based on the weather information; if so, dynamically extracting deviation correlation characteristics and inputting the deviation correlation characteristics into a compensation signal generator to obtain a load deviation compensation value; and superposing the baseline prediction value and the compensation value and outputting a final load prediction correction result. By designing a two-channel architecture in which baseline prediction and dynamic compensation are parallel and performing whole-process tracking and simulation on major weather events in combination with a deviation path diagram, accurate and forward-looking compensation on load deviation is realized, the overall precision and timeliness of load prediction during major weather are improved, and the load prediction efficiency is improved. And the scheduling reliability and the operation safety level of the power grid in the extreme weather are obviously improved.

The application relates to a device and method for electrostatic induction and sound surface wave mask electrolytic machining, belonging to the electrolytic machining field. The pump, the liquid storage tank and the electrolytic tank are connected to realize electrolyte circulation. The various components in the electrolytic tank are riveted. The anode and cathode assemblies and the shielding induction electrode assembly are inserted into the electrolytic tank. The positive and negative poles of the power supply are connected with the anode and cathode plates in the anode and cathode assemblies respectively, and the workpiece arranged in the induction electrode assembly is arranged in the electric field between the anode and cathode plates. The piezoelectric ceramic is attached to the base plate of the induction electrode assembly, and the signal generator and the power amplifier are connected with the piezoelectric ceramic. Based on the device, the piezoelectric ceramic is connected with a megasonic driving voltage to generate a surface wave on the surface of the workpiece; the anode and cathode plates are connected with direct current, and the workpiece is arranged in the electric field formed by the anode and cathode plates, so that the surface to be machined of the workpiece is subjected to oxidation reaction, and the non-machining surface is subjected to reduction reaction, thereby realizing wireless induction machining of the workpiece. The application has the advantages of simple operation, re-distribution of the electric field, enhancement of mass transfer, improvement of mask electrolytic machining precision, arrangement of multiple workpieces in the electric field formed by the anode and cathode plates, and substantial improvement of mask electrolytic machining efficiency.

According to some embodiments, an ear-worn device, e.g., a hearing aid, is provided that operates to monitor the health of a wearer of the ear-worn device based on an audio signal detected by the ear-worn device. In some embodiments, a method of monitoring the health of the wearer of the ear-worn device includes: detecting the audio signal with a microphone of the ear-worn device; processing the detected audio signal using a processor of the ear-worn device; and outputting, from an output signal generator of the ear-worn device, a generated output audio signal. In some embodiments, processing the detected audio signal includes: extracting data indicative of a health event associated with the wearer by processing the detected audio signal with a machine learning model; generating the output audio signal based on the detected audio signal; and outputting the data indicative of the health event.

A switched-mode power supply includes: a Buck converter; and a control circuit for the Buck converter, which includes: a switching unit configured to generate a switching control signal based on a feedback voltage of the Buck converter and a compensation ramp voltage; a transconductance amplifier, where a first input terminal and a second input terminal of the transconductance amplifier are configured to receive a reference voltage and the feedback voltage, respectively; a switch coupled between an output terminal of the transconductance amplifier and a first node, where the switching unit is coupled between the first node and the Buck converter; a compensation control circuit coupled to a control terminal of the switch and configured to open or close the switch based on a first signal representative of a current flowing through an inductor of the Buck converter; and a ramp signal generator configured to generate the compensation ramp voltage.

Provided is a radio transmitter test system that enables accurate measurement of reflected wave power of an antenna. A radio transmitter test system includes: a power amplifier that amplifies power of a high-frequency signal from a signal generator; a simulative antenna for which a voltage standing wave ratio is variable and that is connected to a coaxial cable in place of an antenna; a directional coupler that is connected between the power amplifier and the simulative antenna, couples the high-frequency signal to the simulative antenna, and outputs traveling wave power and reflected wave power between the power amplifier and the simulative antenna; a power meter connected downstream of the directional coupler; and a control device, wherein the control device calculates, for each voltage standing wave ratio of the simulative antenna, a correlation coefficient indicating a correlation between traveling wave power and reflected wave power of the simulative antenna and traveling wave power and reflected wave power measured by the power meter, and calculates reflected wave power of the antenna by correcting, with the correlation coefficient, the traveling wave power and the reflected wave power measured by the power meter in a state where the simulative antenna is replaced by the antenna.

The invention relates to the technical field of mineral exploration, in particular to a high-precision electromagnetic method mineral exploration device suitable for complex terrains, which comprises a self-adaptive mobile frame, and an electromagnetic detection module, a data processing and transmission module, a composite energy module and a central control module are arranged on the self-adaptive mobile frame. According to the high-precision electromagnetic method mineral exploration device suitable for the complex terrain and the detection method, through the combined design of the track assembly, the electric hydraulic rod and the shock absorber, laser radar terrain scanning and path planning are utilized, and autonomous movement and horizontal keeping of the complex terrain are adapted; non-contact electromagnetic detection is adopted, deep and shallow detection is covered by a multi-frequency signal generator, the anti-interference capability is improved according to electromagnetic shielding and adaptive filtering processing, mineral product space distribution and reserve estimation is realized through convolutional neural network imaging, and false positive signals are eliminated through iterative optimization.

The invention belongs to the technical field of pipeline stress nondestructive testing, and particularly relates to a pipeline axial region stress quantitative evaluation system and method based on an alternating current electromagnetic field. According to the pipeline axial region stress quantitative evaluation system and method based on the alternating current electromagnetic field, detectors arranged in a pipeline in an array mode are selected, and stress data transmission is achieved through an aviation wire and an aviation connector; and the electronic processing module is fixed through the stainless steel cabin body framework, so that the full-circumferential detection, acquisition and processing of the internal stress signal of the pipeline are realized. The stress quantitative evaluation system comprises an inner detection cabin, a detection array formed by a plurality of detection probes, and an upper computer. And the inner detection cabin body comprises a cabin body framework, and a signal generator, a power supply module, an effective value processing module and a data storage module which are mounted in the cabin body framework. The detection probe comprises a probe outer shell, a probe inner shell, a magnetic field sensor, a magnetic core and an excitation coil.

The invention relates to the technical field of signal testing, and provides a Web-based PCIe signal testing method, device, system, equipment and medium, and the method comprises the steps: receiving a structured test task file uploaded by a user based on a Web front end, analyzing and extracting a to-be-tested combination parameter, and generating a test task queue; for each test task in the test task queue, calculating a target pulse count value required by PCIe preset parameter switching of the to-be-tested device, controlling the signal generator to output a corresponding target pulse signal, and triggering the to-be-tested device to be switched to a target state; for each test task, configuring oscilloscope parameters, loading a matched link loss simulation file, and controlling an oscilloscope to automatically collect and standardly store waveform data; automatically analyzing the waveform data, and extracting key index data; and filling the key index data into the test report template to generate a target test report. Through the technical scheme, the test efficiency is improved, and the accuracy and consistency of the test are ensured.

The present disclosure discloses a control circuit and a control method for a multiphase power supply and the multiphase power supply. The control circuit includes a current reference signal generator and a controller. The current reference signal generator is configured to adjust a first compensation signal according to a first scaling factor and a first voltage signal, so that the first compensation signal follows the first voltage signal in a steady state, and a current reference signal is obtained according to the first compensation signal and the first voltage signal. The controller is configured to obtain a control signal for each phase power conversion circuit according to the current reference signal to control each phase power conversion circuit to provide a power output to a load. The present disclosure can improve a phase-conversion stability of the multiphase power supply, and can achieve fast and accurate control of the multiphase power supply.

The invention discloses a multi-mode nanometer measurement system and method based on terahertz scattering type scanning near-field optical microscopy and multi-frequency electrostatic force microscopy, and belongs to the technical field of near-field imaging, the measurement system comprises an AFM main body, a terahertz source, an optical path system, a terahertz detector, a multi-frequency signal generator and two phase-locked amplifiers; terahertz waves emitted by the terahertz source reach the terahertz detector through the optical path system, and near-field optical signals are obtained. The AFM comprises a metal coating probe; the multi-frequency signal generator generates sinusoidal signals with frequencies of omega1 and omega2; a sample is placed on the scanner, and the cantilever beam is controlled to vibrate at the frequency omega 1; an alternating voltage with the frequency of omega 2 is applied to a metal coating probe arranged at the top end of the cantilever beam; laser emitted by the laser is reflected to the light spot position detector through the cantilever beam, and morphology and electrostatic force signals are obtained through the two lock-in amplifiers respectively. According to the invention, a morphology signal, an optical signal and an electrostatic force signal can be synchronously obtained through single scanning.

The application discloses a quantum bit regulation circuit, a quantum chip and a quantum computer, and relates to the field of quantum chip control. Based on different frequency ranges, an external signal generator can output an electric signal including low-frequency control information and / or high-frequency control information to a control matching part through a first integrated control line by using only one control channel; the control matching part couples the electric signal including high-frequency control information with a cross capacitor to make the equivalent coupling capacitance value of the quantum bit equal to a target coupling capacitance value, and / or couples the electric signal including low-frequency control information with a superconducting quantum interference device to form a magnetic field to make the working frequency of the quantum bit equal to a target working frequency. In the case of only one control channel, the control matching part realizes the driving and frequency regulation of the quantum bit, reduces the control channel, provides convenience for the setting of a measurement and control channel, is beneficial to the wiring design and packaging of the quantum chip, and is beneficial to integrated design.

Lidar apparatus includes a light source having a source frequency, an electrical signal generator configured to generate a digitally-coded electrical signal, a modulator configured to impress the digitally-coded signal onto a light beam emitted by the light source, and to convert the digitally-coded output beam of the light source into a multi-dimensional modulated output beam, transmitter optics configured to propagate the multi-dimensional beam toward a target, receiver optics configured to receive the multi-dimensional beam as reflected by the target, an optical demodulator configured to demodulate the reflected multi-dimensional beam, electro-optical conversion circuitry configured to output an electrical signal representing the received reflected multi-dimensional beam, and digital signal processing circuitry configured to compare the electrical signal representing the received reflected multi-dimensional beam to the digitally-coded signal to determine at least one of (a) range, and (b) velocity, of the target.

The present invention provides a plasma processing device for efficiently performing plasma processing. This plasma processing device includes a chamber, a substrate support part disposed in the chamber and including a lower electrode, an upper electrode disposed above the substrate support part, an RF signal generator electrically connected to the upper electrode or the lower electrode and configured to generate an RF signal for generating plasma in the chamber, a voltage signal generator electrically connected to the lower electrode and configured to generate a voltage signal having a voltage pulse sequence, a rectifier element electrically connected between a ground potential and the upper electrode, and a voltage phase adjustment element electrically connected, between the ground potential and the upper electrode, in series with the rectifier element.