47results about How to "Small output resistance" patented technology

The invention discloses a charge pump structure for a phase-locked loop circuit, which is used to convert the phase difference signal output by a frequency discriminator or phase detector to the voltage signal so that to control the output signal frequency of a VCO(voltage controlled oscillator). The invention is characterized in that the charge bump structure includes two identical buffer units which is used to convert the single end signal to differential signal and can generate two complementary differential signals on the Up signal and Down signal, and a charge and loop filter unit which are formed by two identical charge pump circuits connected in series and are used to convert the complementary differential signal to the voltage signal. The charge pump structure of the invention eliminates the influence of parasitic capacitance, reduces the mismatch degree of the transistor during manufacture and keeps the relative matching of the transistor.

The invention discloses a micro-grid multi-inverter parallel voltage control method for droop control of robust power. The method comprises the following steps of: specific to each inverter in a micro-grid, computing and synthesizing an inverter output reference voltage by adopting a robust power droop controller; and introducing virtual complex impedance containing a resistance component and an inductive impedance component, and keeping inverter output impedance in a pure resistance state under a power frequency condition by adopting a multi-loop voltage control method based on virtual impedance and quasi-resonance PR (Proportional-Resonant) control, thereby realizing micro-grid multi-inverter parallel running and power equation, wherein the robustness of a micro-grid parallel system on numeric value computing errors, parameter drift, noise interference and the like is enhanced. Due to the adoption of the method, the defects of larger loop current of a parallel system, non-uniform power distribution and the like caused by the inductivity of the impedance output by inverters in the conventional droop method are overcome; and the method is suitable for multi-grid parallel uniform current control in a low-voltage micro-grid.

The invention discloses a quick transient response CMOS (Complementary Metal Oxide Semiconductor) low-dropout regulator. The inverted input end of an error amplification circuit is connected with reference voltage Vref, the in-phase input end of the error amplification circuit is connected with the sampling output end Vf of a sampling resistor circuit, and the output end of the error amplification circuit is connected with the gate of a power tube through a conversion rate increasing circuit. The positive power end of the error amplification circuit, the positive power end of the conversion rate increasing circuit and the source of the power tube are connected to form the input end Vin of a regulator body. The drain of the power tube and the positive power end of the sampling resistor circuit are connected to form the output end Vout of the regulator body. The negative power end of the error amplification circuit, the negative power end of the conversion rate increasing circuit and the negative power end of the sampling resistor circuit are connected to form the ground end GND of the regulator body. The quick transient response CMOS low-dropout regulator is higher in conversion rate and quicker in transient response.

The invention relates to a semiconductor gas sensor with a flat sandwich construction and its manufacturing method, which resolves problems of large resistance, low conductivity and high heating consumption in existed constructions of semiconductor sensor. In this sensor, there is a heater etched on substrate, a sensitive source etched on insulating layer, insulating layer plated on heater, sensitive film plated on sensitive source and a perforated electrode set on sensitive film. The manufacturing method contains steps of selecting and washing by substrate, fabricating heater, insulating layer and sensitive electrode etc. The invention has merits of small resistance, high conductivity and low heating consumption, which has high precision in manufacturing technology.

A twelve-lead electrocardiosignal synchronous acquisition module belongs to the technical field of medical devices and solves the problems that the existing twelve-lead electrocardiogram adopts wired measurement, so the detection is inconvenient and the measuring equipment is high in cost. The twelve-lead electrocardiosignal synchronous acquisition module comprises a body surface electrode, an electrocardiosignal input circuit, a differential amplification circuit, a filter circuit, a lead selection circuit, a signal amplification circuit, a analog-digital conversion circuit, a single chip computer and a level switching circuit all connected in sequence. When in use, the twelve-lead electrocardiosignal synchronous acquisition module disclosed by the invention is connected with an embedded WIFI module, and then connected with a computer in a wireless manner, so a low-cost domestic twelve-lead electrocardiogram wireless measuring system is established, domestic wireless measurement of the electrocardiogram is realized, the electrocardiogram detection is convenient, and the detecting equipment is low in cost.

Disclosed is a room temperature ammonia (NH3) sensor based on DPA-Ph-DBPzDCN and gold interdigital electrodes and preparation method therefor, belonging to the technical field of gas sensors. The roomtemperature NH3 sensor is composed of an Al2O3 ceramic plate, gold interdigital electrode bases, and a DPA-Ph-DBPzDCN sensitive material thin film from bottom to top. The preparation method comprisesthe following steps: preparing a DPA-Ph-DBPzDCN sensitive material through Suzuki coupling reaction; separately preparing nickel and gold on the Al2O3 ceramic substrate to prepare interdigital electrodes by sputtering; and preparing the DPA-Ph-DBPzDCN sensitive material on the interdigital electrodes by using a spin coating method. According to the room temperature NH3 sensor based on DPA-Ph-DBPzDCN and gold interdigital electrodes and preparation method therefor, a novel organic material DPA-Ph-DBPzDCN is used as a sensitive material, so that the working temperature of the sensor is effectively reduced, and ammonia gas can be detected at room temperature; and good selectivity and stability are achieved besides a rapid response speed for ammonia gas at room temperature.

The invention discloses a charging circuit and a charger using the charging circuit, comprising a generator; a voltage reducing circuit, a current controller, a mode selector, and a monitor. The invention is characterized in that the voltage reducing circuit reduces the output voltage of the generator to predetermined voltage; the current controller controls the charging current supplied to a secondary battery by the voltage reducing circuit according to the electric quantity produced by the generator; the mode selector selects charging mode; the monitor monitoring the stored electric quantity; in the process of charging, the voltage reducing circuit receives the output of the generator by high voltage and small current, and charges the secondary battery by low voltage and high current.

The invention relates to a polymer solar cell. The polymer solar cell sequentially comprises a cathode layer, a cathode interface layer, a photosensitive layer, an anode interface layer and an anode layer, wherein the cathode interface layer is an inorganic semiconductor nanocrystalline-conjugated polymer composite material layer. The cathode interface layer is specifically a ZnO-PFEP (phosphate ester polyfluorene) composite material layer. According to the polymer solar cell, the ZnO-PFEP composite cathode interface layer is arranged between the cathode layer and the photosensitive layer, and the mass ratio of ZnO to PFEP in the interface layer is controlled, so that the electrical conductivity of the cathode interface layer can be effectively increased, the bulk resistance of the cathode interface layer is reduced, the electron output resistance is decreased, furthermore, the short-circuit current, open-circuit voltage, fill factor and energy conversion efficiency of the cell are improved, and the electron transportation and collection are benefited.

The invention discloses a transimpedance amplifier applied to a high-speed optical receiver and a design method. The transimpedance amplifier comprises a three-level high gain amplifier A and a feedback resistor Rf. The three-level high gain amplifier A comprises a first-level amplifier A1, a second-level amplifier A2 and a third-level amplifier A3. The output end of the first-level amplifier A1 is connected with the input end of the second-level amplifier A2. The output end of the second-level amplifier A2 is connected with the input end of the third-level amplifier A3. Two ends of the feedback resistor Rf are connected with the input end of the first-level amplifier A1 and the output end of the third-level amplifier A3. According to the transimpedance amplifier, a structure of reducing bandwidth and then increasing the bandwidth is employed in the amplifier of the TIA (Transimpedance Amplifier), so under the condition of ensuring the bandwidth required by a system transmission rate, the transimpedance gain of the TIA is improved, and the equivalent input noise of the TIA is reduced.

The invention relates to a difference common collector amplifying circuit which is a device of an amplifying signal current for decreasing the distortion factor of a power amplification circuit. At present, a well-known current amplifying circuit of a station amplifier generally adopts an OCL circuit, in which the utility ratio of a power supply is higher, the direct coupling is realized, the circuit is simple and the power is big, but the performance of common-mode interference resistance of the circuit is reduced because non-equilibrium design is adopted, and the distortion is larger. Based on a traditional monotube common collector amplifying circuit, the difference common collector amplifying circuit introduces a difference structure, and a fully symmetrical and balanceable circuit structure is used for resisting the common-mode interference. The invention can be mainly used in the fields of low-frequency signal current amplification, aural signal current amplification, amplifier impedance match, an amplifier high input impedance input circuit, an amplifier low input impedance output circuit, single end-balanced signal transformation, etc.

The invention discloses an extensible precision source meter which comprises a power supply unit, an external interface unit, a main power path unit and an analog control module unit located between the external interface unit and the main power path unit. The analog control module unit further comprises an FPGA (Field Programmable Gate Array) main controller, a voltage digital-to-analog converter, a current digital-to-analog converter, a current feedback circuit, a voltage sampling and feedback circuit, a first error amplifier, a second error amplifier and an MOS (Metal Oxide Semiconductor) driving module; the amplifier is used for amplifying a voltage error signal from the first error amplifier and a current error signal from the second error amplifier; and the buffer driving circuit is positioned between the MOS driving module and the output regulator. The extensible precision source meter overcomes the unacceptable technical problems that in the prior art, high-voltage and large-current output cannot be achieved, expandability is poor, load adaptability is poor, output is prone to oscillation under certain load conditions, and voltage stabilization cannot be achieved.

The invention discloses a cellular photovoltaic power station. In the invention, one multi-input and single-output node inverter are connected into a small power node, the outputs of a plurality of small power nodes are connected in parallel to form the cellular photovoltaic power station. The node inverter of the cellular photovoltaic power station is provided with a plurality of photovoltaic module input interfaces and an inversion output port, each input interface corresponds to independent maximum power point tracking DC / DC converting circuit, and a microcontroller regulates a DC / DC conversion state according to the maximum power point tracking algorithm; conversion outputs of the whole photovoltaic modules on the interface are directly connected in parallel to realize integration of output power of the plurality of photovoltaic modules; and the integration power of the module is output by the inversion of one DC / AC. The invention combines the advantages of an integrated inversion photovoltaic power station and a micro-inverter photovoltaic power station and has high promotion value.

The present invention discloses an electrode falling detection circuit. The electrode falling detection circuit comprises an impedance detection unit and a processor; the impedance detection unit is connected with electrodes and used for receiving impedance detection signals, also uses the impedance detection signals to detect electrode-loaded impedance and generates impedance signals; and the processor is connected with the impedance detection unit and used for providing the impedance detection signals for the impedance detection unit, calculates an impedance value according to the impedancesignals generated by the impedance detection unit and judges whether the electrodes fall off from a human body or not according to the impedance value. By detecting the electrode-loaded impedance value, if the impedance value is larger than a threshold value, the electrodes are considered to fall off from the human body and detection of falling-off of the electrodes from the human body is achieved.

The invention discloses a transient enhancement circuit applied to a low-power-consumption fully-integrated low dropout regulator. The transient enhancement circuit comprises an LDO control main loop, an undershoot suppression circuit, an undershoot recovery circuit, an overshoot suppression circuit and an overshoot recovery circuit. According to the circuit, overshoot suppression and transient enhancement of output voltage are realized by detecting transient voltage change of an output node of a power MOS (Metal Oxide Semiconductor) tube: when light load and heavy load of load current are instantaneously switched, a corresponding suppression circuit and a corresponding recovery circuit work, and corresponding pull-up current and pull-down current are provided, so that overshoot of the output voltage is suppressed, and recovery is accelerated. Moreover, when the output voltage is stable, all pull-up MOS tubes and pull-down MOS tubes of the transient enhancement circuit are turned off, and excessive static power consumption is not increased. A simulation result shows that the response capability of the low-power-consumption fully-integrated low-dropout linear regulator to transient change of load current can be remarkably improved.

The invention provides a current measurement method, power supply equipment and a power supply chip. The method is applied to a power supply chip. The power supply chip includes an output module and acontrol module, wherein the output module comprises a first switching element and a second switching element; the output module supplies power to a load through an inductance element and a capacitance element which are externally coupled to the power supply chip. The method comprises the steps of providing a switching signal for the first switching element, and acquiring a voltage signal of the inductance element, wherein the voltage signal comprises an input voltage signal and an output voltage signal of the inductance element; obtaining a current ripple characteristic parameter of the inductance element, and determining an inductance value of the inductance element based on the current ripple characteristic parameter; and determining a current signal of the inductance element based on the voltage signal, the inductance value, and the switching signal. Through the embodiment of the invention, the current measurement precision can be improved, and the power supply efficiency is further improved.

A method for preparing displacement transducer of radio-frequency single electronic transistor type includes preparing beams being fixed at two ends and single electronic transistor on SOI substrate, utilizing nanoscale beams being fixed at two ends as sensitive elements and utilizing radio-frequency single electronic transistor as sensing element to form fast supersensitive displacement transducer.

The invention discloses a structure and a preparation method of an MOSFET device based on a diamond substrate, and belongs to the technical field of microelectronics. The structure comprises a diamond substrate, hydrogen terminal layers arranged at the upper end and the lower end of the diamond substrate, a source electrode and a drain electrode arranged on the two sides of the diamond substrate respectively, gate dielectric layers arranged on the surfaces of the hydrogen terminal layers and gate electrodes arranged on the surfaces of the gate dielectric layers. According to the double-gate diamond device formed by the method, the maximum saturation current and transconductance of the diamond device can be improved under the condition of keeping the threshold voltage basically unchanged, the switching ratio of the device is improved by nearly three orders of magnitudes, the output resistance of the device is reduced, the cut-off frequency of the diamond device is greatly improved, and the characteristics of simple manufacturing process and good repeatability are achieved.

The invention belongs to the technical field of integrated circuits, and relates to a buffer circuit used for an LDO. Compared with a traditional LDO circuit, in the buffer circuit used for the LDO, the buffer circuit is added; the buffer circuit can improve the driving capacity of an error amplifier, so that the transient response of the LDO is drastically improved; besides, since the buffer circuit is composed of a source follower, the source follower has an extremely low output resistance, and therefore, a pole P3 generated by an output end of the error amplifier can be pushed to a higher frequency, so that the stability of the circuit is not influenced by the pole P3; more importantly, in the buffer circuit, through the design of the circuit structure, the quiescent current of the buffer is reduced, which has very significant importance in the reduction of the overall power consumption of the LDO circuit.

The invention discloses an input and output circuit for a solid-state relay and the solid-state relay. The relay has the advantages of high load capacity, high reliability, high insulation resistance,high overload capacity, high reliability and high salt spray resistance. The control speed is high, and the driving energy requirement is low; the overall dimension is designed to be 21.8 mm*12.8 mm*10 mm. The solid-state relay provided by the invention is compact in structure, small in size and light in weight, and the weight of the solid-state relay provided by the invention is less than 8g; under the limitation of volume and weight conditions, small output resistance, low power consumption and high output power are ensured.

The invention discloses a voltage buffer applied to an SAR (Successive Approximation Register) ADC (Analog to Digital Converter). The voltage buffer comprises an error amplifier, a voltage buffer output circuit and a level detection circuit, wherein the voltage buffer is used for providing a reference voltage to a capacitive DAC of the SAR ADC, has high capability of driving a large-capacitance load, and can meet the requirement that the reference voltage needs to quickly restore due to a change of the capacitance load. The voltage buffer also has rapid starting capability; required reference voltage can be quickly built by the voltage buffer when the circuit is electrified to start, and the time that the SAR ADC enters a normal working state from a dormant state is shortened, so that the response speed of the SAR ADC is improved. Compared with a traditional voltage buffer applied to the SAR ADC, the voltage buffer disclosed by the invention has the advantages that the capability of driving the capacitance load is higher, and the power consumption is lower.

The invention discloses a fast transient response CMOS low-dropout linear voltage regulator. The inverting input terminal of the error amplification circuit is connected to the reference voltage Vref, and the non-inverting input terminal of the error amplification circuit is connected to the sampling output terminal Vf of the sampling resistance circuit. The output terminal of the error amplifier circuit is connected to the gate of the power tube through the slew rate enhancement circuit; the positive power terminal of the error amplifier circuit, the positive power terminal of the slew rate enhancement circuit and the source of the power tube are connected to form the input of the regulator body terminal Vin; the drain of the power tube is connected to the positive power supply terminal of the sampling resistor to form the output terminal Vout of the voltage regulator body; the negative power supply terminal of the error amplifier circuit, the negative power supply terminal of the slew rate enhancement circuit and the negative power supply terminal of the sampling resistor After the terminals are connected, the ground terminal GND of the voltage regulator body is formed. The invention has higher conversion rate and transient response.

The invention discloses a planar room-temperature NH3 sensor based on a TPA-DCPP (7,10-bis(diphenyl amino) phenyl-2,3-dicyanopyrazino phenanthrene) organic sensitive film, and a preparation method thereof, and belongs to the technical field of gas sensors. The sensor consist of an Al2O3 ceramic plate, a gold interdigital electrode and a TPA-DCPP organic sensitive material film from bottom to top in sequence. The preparation method for the planar room-temperature NH3 sensor comprises the following steps that: firstly, through Suzuki coupled reaction, preparing a TPA-DCPP organic sensitive material; then, through a sputtering method, independently preparing nickel and gold to the Al2O3 ceramic substrate to prepare the interdigital electrode; and then, utilizing a spin-coating method to prepare the TPA-DCPP organic sensitive material on the interdigital electrode. By use of the sensor and the preparation method, the working temperature of the sensor is effectively lowered, the NH3 can bedetected under a room temperature condition, and the ppb(part per billion)-magnitude detection of the NH3 can be realized under high humidity (98%RH (Relative Humidity)). In addition to a high response speed for the NH3 at the room temperature, the sensor disclosed by the invention also has good selectivity and stability.

The invention discloses an output buffer circuit which has noise resistant and load adaptive capacity. The buffer circuit comprises a pre-driver, a first charge and discharge circuit and a second charge and discharge circuit. The pre-driver provides the first charge and discharge circuit and the second charge and discharge circuit with a drive signal so as to enable the first charge and dischargecircuit and the second charge and discharge circuit to be electrified at different times; the PMOS tube which is connected in a diode manner and the NMOS tube which is connected with a diode in the first discharge circuit cut off automatically when the charge and discharge is almost over, thereby enhancing a resistance which can be seen from an output end and ensuring the circuit has excellent noise resistant property. Additionally, the structure of the invention can lead the electrification time of two discharge circuits to take up the proportion size of the overall switching process, that is, the driving capacity provided by the circuits changes along with the change of a load, so that load adaptive capacity is possessed. Therefore, the invention has the advantages of low consumption, noise resistance, and load adaptive property.

The invention discloses an error amplifier for a large-current DCDC power supply module. The error amplifier comprises a soft start circuit and an error amplifier main circuit. The soft start circuit is used for stabilizing rising voltage during starting; the error amplifier main circuit is used for comparing the feedback voltage VFB with the reference voltage VREF, and the error amplifier main circuit and the compensation capacitor form a secondary dominant pole far away from the original point. The error amplifier is applied to a large-current DCDC power module, the pole position of the output end of the error amplifier is far away from the original point position and serves as a secondary dominant pole of a power module system by increasing the transconductance of the error amplifier and reducing the output resistance technically, and the system stability is guaranteed.

The invention provides an ultra-low noise signal amplification circuit for a capacitive ocean inert material electrode. The ultra-low noise signal amplification circuit comprises a chopping modulation circuit which is used for modulating an ultra-low frequency broadband weak signal into a high-frequency signal to avoid flicker noise of a subsequent signal processing circuit; a potential impedance matching circuit which is used for providing reference potential of a chopping modulation control signal and matching impedance of an electrode; a high input impedance differential alternating current amplification circuit which is used for performing low-noise differential amplification processing on a signal and converting a differential signal into a single-ended signal; a chopping demodulation circuit which is used for demodulating the high-frequency signal into a low-frequency signal and recovering an amplified low-frequency broadband signal; a low-pass filter circuit which is used for filtering high-frequency noise generated by modulation and demodulation; and a high input impedance direct current amplification circuit which is used for impedance matching of circuit output. The signal amplification circuit provided by the invention is an ultra-low noise signal amplification circuit for impedance matching of a capacitive electrode, and is suitable for signal detection of an easily polarized capacitive ocean inert material electrode.

The present invention discloses an electrode falling detection circuit. The electrode falling detection circuit comprises an impedance detection unit and a processor; the impedance detection unit is connected with electrodes and used for receiving impedance detection signals, also uses the impedance detection signals to detect electrode-loaded impedance and generates impedance signals; and the processor is connected with the impedance detection unit and used for providing the impedance detection signals for the impedance detection unit, calculates an impedance value according to the impedancesignals generated by the impedance detection unit and judges whether the electrodes fall off from a human body or not according to the impedance value. By detecting the electrode-loaded impedance value, if the impedance value is larger than a threshold value, the electrodes are considered to fall off from the human body and detection of falling-off of the electrodes from the human body is achieved.

The invention discloses a CMOS reference voltage buffer with low output resistance. The CMOS reference voltage buffer with low output resistance includes a single-pole high-gain OTA, a power transmission PMOS transistor Tp, a first feedback resistor R1 and a second feedback Resistor R2, the single-pole high-gain OTA includes a voltage source VDD, a first PMOS transistor P1, a second PMOS transistor P2, a first NMOS transistor N1, a second NMOS transistor N2, a third NMOS transistor N3, and a fourth NMOS transistor N4 , the fifth NMOS transistor N5, the sixth NMOS transistor N6, the seventh NMOS transistor N7, the eighth NMOS transistor N8, the ninth NMOS transistor N9 and the tenth NMOS transistor N10. The reference voltage buffer provided by the present invention has a very low output impedance at a low frequency, and the extra circuit overhead is small, which is beneficial to maintain low power consumption.

The embodiment of the invention discloses a CAN bus communication system. The CAN bus communication system comprises a constant current source and a group of differential transmission lines, wherein the differential transmission lines comprise a CANH line and a CANL line. The positive electrode end of the constant current source is electrically connected with the CANL line, and the negative electrode end of the constant current source is electrically connected with the CANH line. According to the embodiment of the invention, the external constant current source can provide a reverse current for the CAN bus, which is equivalent to reducing the output resistance of the bus when the hidden level is transmitted, so that the time for the bus to jump to the hidden level when the bus has relatively large parasitic capacitance can be obviously reduced, and further the error rate is reduced and the transmission accuracy is improved. Meanwhile, the CAN bus communication system is provided with a terminal resistor, the positive electrode end of the constant current source is electrically connected with the CANL line, and the negative electrode end of the constant current source is electrically connected with the CANH line, so that the steady-state voltage of the CAN bus communication system is reduced to a negative value, the difference between a hidden level threshold value and the steady-state voltage is increased, the error rate is further reduced, and the accuracy of bus signal transmission is improved.

The invention discloses a short circuit detection circuit, a short circuit protection circuit and a switching power supply circuit. The short circuit detection circuit comprises a sampling circuit which is connected with a communication line, avoltage follower, a controller and avoltage stabilizing circuit, wherein the sampling circuit is used for collecting the working voltage of the communication line; the input end of the voltage follower is connected with the sampling circuit, and the output end of the voltage follower is connected with the input end of the controller; the controller is used for judging whether the communication line is short-circuited or not according to the voltage output by the voltage follower; one end of the voltage stabilizing circuit is connected with the output end of the voltage follower; and the voltage stabilizing circuit has a charging state and a discharging state. According to the arrangement, when the communication line works normally and the voltage fluctuates, the voltage stabilizing circuit can enable the voltage obtained by the input end of the controller to be maintained at a high value, so that the condition of triggering short circuit protection is met, and the reliability of the short circuit detection circuit is improved.

The invention discloses a low-resistance transmission circuit based on a CVP probe active integration method. The low-resistance transmission circuit consists of a CVP probe unit, an integration unit and an impedance conversion unit, wherein high-voltage pulse square waves are input into an input end of the CVP probe unit; high resistance is set between integration signal output circuits of an RC integration circuit; low resistance is set between output circuits of the impedance conversion unit; and the output circuits of the impedance conversion unit are directly connected to a signal transmission line. Through adoption of the low-resistance transmission circuit, a low-resistance transmission technology based on the CVP probe active integration method is realized under the situation that technical problems in a general integration method are solved completely. An active integrator is directly connected with a CVP probe output end, so that the influence of a long cable on a differential signal high-frequency component is eliminated, and the problem that general test measures such as integration signal transmission (long cables or optical fibers), impedance matching, signal shutting or overlapping cannot be taken on the aspect of testing technology is well solved.