19results about "Limiting amplitude using diodes" patented technology

The application provides an amplifier current-limiting control method for fusing power regulation and load characteristic monitoring, comprising: realizing controllable front-stage signal through differential input and band-pass clamping, establishing voltage, current and multi-point temperature monitoring and combining overvoltage detection to generate out-of-limit indication, setting voltage and current upper limit in silicon-controlled voltage regulating module and executing voltage reduction and current limiting, realizing orderly switching through front-stage shutdown and relay stable control when impedance gear is switched, keeping front-stage closed and shutting down power drive when out-of-limit continues to exist, and until monitoring quantity recovers to safe range. Through the collaborative design of "source power limiting, state monitoring, orderly switching and linkage protection", the application effectively suppresses transient impact, shortens protection response time, reduces distortion accumulation, and realizes the unity of high-power output and high reliability of wide-band multi-gear amplifier.

The disclosure provides a self-detection multi-stage limiter based on micro-assembly and a preparation method thereof. The limiter comprises a ceramic tube shell, a substrate, and a front-stage power detection processing circuit and a rear-stage leakage power processing circuit fixed on one side surface of the substrate based on a micro-assembly process. The rear-stage leakage power processing circuit is a monolithic microwave integrated circuit, and the monolithic microwave integrated circuit is integrated with M series limiting units in series. Each limiting unit comprises two element strings in reverse parallel connection, and each element string comprises a plurality of gallium nitride Schottky diodes in series connection. The self-detection limiter based on the micro-assembly process can realize a fast response time, clamp the leakage peak power leaked after the front-stage processing by using the rear-stage leakage power processing circuit, and realize flexible adjustment of the amplitude threshold and the leakage level by adjusting the number of limiting unit stages or the number of GaN SBDs in series connection in the limiting unit, so as to facilitate matching of the signal power range and the protection requirements of different use scenarios.

The application provides a limiter circuit, which comprises a plurality of transmission lines connected in series, one end of the transmission lines is used as an input end of a radio frequency signal, the other end of the transmission lines is connected with an input end of an amplifier, and an output end of the amplifier is used as an output end of the radio frequency signal; a limiter branch is connected between adjacent transmission lines and the amplifier in sequence, and the parasitic capacitance of each limiter branch is equal; a limiter bias circuit is electrically connected with each limiter branch, and is used for making the opening power voltage of each limiter branch equal. According to the application, the size of each limiter branch is adjusted according to the uneven distribution of current, so that the current density of each limiter branch is balanced, and the insertion loss and impedance matching can be effectively improved, and the bandwidth is improved under the premise of realizing the current density balance and improving the power protection ability.

The invention relates to the technical field of radio frequency devices, in particular to an amplitude limiter circuit structure integrated with a filtering function by a gallium arsenide process, and the circuit sequentially comprises a 50-ohm microstrip input matching section, a first-stage amplitude limiting filtering unit, a second-stage amplitude limiting filtering unit and an output matching section along a main transmission line, in the first stage, three forward PIN diodes and three reverse PIN diodes are stacked and connected to a main circuit in parallel, high power tolerance and symmetrical amplitude limiting capacity are achieved, and two low-frequency transmission zero points are formed by fusing a micro-strip grounding branch knot and an MIM capacitor resonator; in the second stage, two anti-parallel PIN diodes are matched with a grounding inductor to form a third transmission zero point, three groups of resonant structures are integrated, six transmission zero points are introduced, the filtering performance in a 12-18GHz frequency band is remarkably enhanced, a PIN diode parasitic capacitor and a microstrip inductive structure are skillfully utilized by the circuit to cooperatively realize filtering, extra passive elements are not needed, and the cost is low. The method is suitable for integrated protection of sensitive devices in a high-frequency radar and communication system.

The invention discloses a DC-DC converter control circuit suitable for a high pulse load, and belongs to the field of DC-DC converter control circuits, and the DC-DC converter control circuit comprises a voltage outer loop compensation circuit, a current amplitude limiting circuit, a current inner loop compensation circuit and a pulse width modulation circuit. The output end of the voltage outer loop compensation circuit is connected with one end of the current amplitude limiting circuit, the other end of the current amplitude limiting circuit is connected with the input end of the current inner loop compensation circuit, and the output end of the current inner loop compensation circuit is connected with the pulse width modulation circuit. According to the invention, the current amplitude limiting circuit and the loop compensation circuit are utilized to realize closed-loop regulation of the output inductive current, so that the capacity of outputting the capacitor of the converter is improved, the current response speed is accelerated, the stable output capacity and reliability of the converter are ensured, and the adaptability of a high-pulse load working condition is improved.

The invention discloses an active amplitude limiting and filtering integrated module for a T / R assembly of phased array equipment. The module comprises first to fourth level LC resonance circuits, a PIN tube, a control circuit, an input port, an output port and a control port. The input port is connected with one end of the first-stage LC resonance circuit, and the other end of the first-stage LC resonance circuit is sequentially connected with one end of the second-stage LC resonance circuit, the anode of the PIN tube, one end of the third-stage LC resonance circuit and one end of the fourth-stage LC resonance circuit; the other end of the second-stage LC resonance circuit is grounded, the cathode of the PIN tube is grounded, the other end of the third-stage LC resonance circuit is grounded, and the other end of the fourth-stage LC resonance circuit is connected with an output port; one end of the control circuit is connected with the anode of the PIN tube, and the other end is connected with the control port. According to the invention, the integrated design is adopted, the size is small, the insertion loss is small, the anti-emission leakage signal burning performance of the receiving channel of the T / R assembly is improved, and the safety and stability of the T / R assembly are enhanced.

Provided is a cascade connection type amplifier circuit in which overvoltage input is suppressed. An amplifier circuit (1) is provided with: an input terminal (101) and an output terminal (102); an FET (11) having a gate terminal (g1), a drain terminal (d1), and a source terminal (s1); an FET (12) having a gate terminal (g2), a drain terminal (d2), and a source terminal (s2); a diode (511) having a first anode terminal and a first cathode terminal; and a diode (512) having a second anode terminal and a second cathode terminal, the gate terminal (g1) being connected to the input terminal (101), the drain terminal (d1) being connected to the source terminal (s2), the drain terminal (d2) being connected to the output terminal (102), the first anode terminal and the second cathode terminal being connected to a first path connecting the input terminal (101) and the gate terminal (g1), and the second anode terminal and the first cathode terminal being connected to the drain terminal (d1).

This invention discloses an RF power amplifier module and its power protection method. The module includes a controller chip, an RF power amplifier chip, and a filter connected in sequence. The controller chip is connected to a power supply voltage VCC that powers the RF power amplifier chip. The controller chip detects the power supply voltage VCC and outputs a limiting bias voltage that increases with the increase of the power supply voltage VCC when VCC exceeds a set threshold. The RF power amplifier chip includes a limiting circuit and a power amplifier unit. The limiting circuit limits and attenuates the RF input signal according to the limiting bias voltage to obtain an attenuated RF signal. The power amplifier unit amplifies the attenuated RF signal before outputting it. The filter filters the amplified RF signal to output an RF signal in the target frequency band. This invention can adaptively change the limiting degree according to the power level and improve the speed of power detection.

The application provides a limiter circuit, which comprises a plurality of transmission lines connected in series, one end of the transmission lines serving as an input end of a radio frequency signal, the other end of the transmission lines being connected with an input end of an amplifier, and an output end of the amplifier serving as an output end of the radio frequency signal; a limiter branch connected between adjacent transmission lines and the amplifier in series, each limiter branch comprising a first symmetric branch and a second symmetric branch, the first symmetric branch and the second symmetric branch in each limiter branch being symmetrically distributed on both sides of the transmission line, so that the parasitic capacitance of each limiter branch is consistent and evenly distributed; and a bias control circuit connected with the first symmetric branch and the second symmetric branch in each limiter branch, so that the current and the density of each limiter branch are the same under the same size. The limiter circuit of the application improves the insertion loss and the effective power tolerance of the limiter circuit.

The invention relates to the technical field of radio frequency front ends, in particular to a broadband amplitude-limiting low-noise amplifier. On the basis of a traditional broadband amplitude-limiting low-noise amplifier, an input matching network unit and an amplitude limiter unit of a circuit are subjected to innovative topological transformation, and a source-level negative feedback unit is fused, so that noise coefficients in a broadband are remarkably optimized; a parasitic capacitor introduced by an amplitude limiter unit is integrated with an input matching unit, and the parasitic capacitor of the amplitude limiter is absorbed as a part of an input matching network through dynamic conversion of circuit topology according to impedance matching requirements of different working frequencies, so that impedance matching of a target frequency is completed by using parasitic parameters, and the impedance matching of the target frequency is completed by using the input matching unit. And the introduction of extra noise to a signal path when a stray capacitor of the amplitude limiter exists independently in the traditional design is avoided, and the noise deterioration phenomenon caused by the stray parameter of the amplitude limiting unit is reduced fundamentally.

A differential amplifier system is provided for receiving first and second input signals and generating first and second differential output signals. The system includes: a differential amplifier for receiving the first and second input signals, providing a first output current at a first current channel, and providing a second output current at a second current channel; a cascode stage for receiving the first and second output currents and generating the first and second differential output signals; and a detector for detecting when the first output current flowing through the first current channel satisfies the first condition, and / or detecting when the second output current flowing through the second current channel satisfies the second condition, wherein a current sink stage is configured to redirect at least a portion of the first and second output currents away from the cascode stage when the first output current satisfies the first condition, and / or redirect at least a portion of the first and second output currents away from the cascode stage when the second output current satisfies the second condition.

The invention discloses a center frequency reconfigurable amplitude limiting filter based on series-parallel topology. The center frequency reconfigurable amplitude limiting filter comprises a main transmission line, a first-stage amplitude limiting circuit, a transmission line TL1, a second-stage amplitude limiting circuit, a frequency reconfigurable unit and a lumped parallel resonator, the frequency reconfigurable unit realizes working center frequency adjustability by adjusting bias voltage VDC; and the second-stage amplitude limiting circuit widens the out-of-band rejection width by introducing a transmission zero point. Compared with an existing amplitude limiting filter, the band-pass filter has the advantages that the out-of-band rejection width is remarkably improved while the frequency reconfigurable function is achieved, and the band-pass filter can be applied to a multifunctional and high-performance radio frequency front-end system.

This invention discloses a limiter chip, which includes a dielectric substrate and a limiting unit disposed on the dielectric substrate. The limiting unit includes a limiter cell disposed on the upper surface of the dielectric substrate and a ground plane that fully covers the back side of the dielectric substrate. The limiter cell includes an input terminal, an output terminal, six limiting stage diodes, four buffer stage diodes, two detection stage diodes, two choke inductors, a tuning capacitor, four ground terminals distributed at the four corners, multiple vias, and multiple transmission lines for connection. Each stage of diodes is grounded using an anti-parallel structure, and different stages are connected using choke inductors. The tuning capacitor is located after the choke inductor between the limiting stage and the buffer stage, connecting it in parallel to ground. This structure is used to limit the input signal. By integrating it onto a chip using integrated circuit technology, it has advantages such as high integration, wide bandwidth performance, wide application range, and low cost.

The invention discloses a radio frequency power amplifier module and a power protection method thereof. The module comprises a controller chip, a radio frequency power amplifier chip and a filter which are connected in sequence, the controller chip is connected with a power supply voltage VCC for supplying power to the radio frequency power amplifier chip, and the controller chip is used for detecting the power supply voltage VCC and outputting an amplitude limiting bias voltage which is increased along with the increase of the power supply voltage VCC when the power supply voltage VCC exceeds a set threshold value; the radio frequency power amplifier chip comprises an amplitude limiting circuit and a power amplifier unit; the amplitude limiting circuit is used for carrying out amplitude limiting attenuation on the radio frequency input signal according to the amplitude limiting bias voltage to obtain an attenuated radio frequency signal; the power amplifier unit is used for performing power amplification on the attenuated radio frequency signal and then outputting the amplified radio frequency signal; and the filter is used for filtering the amplified radio frequency signal so as to output the radio frequency signal of the target frequency band. According to the invention, the amplitude limiting degree can be adaptively changed according to the power, and the power detection speed is improved.

The application discloses a broadband frequency selective limiting system and a radio frequency device, and relates to the technical field of microwave radio frequency devices. Specifically, the application comprises a first input coupling unit, a first limiting component, a second input coupling unit, a second limiting component and an output synthesis unit. The input end of the second input coupling unit is connected with the first isolation end of the first input coupling unit. The output synthesis unit is electrically connected with the output end of the first limiting component and the output end of the second limiting component. Microwave signals of the first frequency band and the second frequency band are finally uniformly converged by the output synthesis unit. Through the cascading mode of the coupling unit and the limiting component reflection mechanism, the application solves the high insertion loss caused by the equal energy division of the traditional power divider and the large size problem caused by the series filter, greatly reduces the cost, and also expands the effective working bandwidth.

The invention relates to the technical field of semiconductor integrated circuits, in particular to a variable resistance circuit based on a variable capacitance diode and an integrated circuit chip, and the circuit comprises a semiconductor device which is provided with a positive electrode, a source electrode and a grid electrode; the first end of the resistor is connected with the source electrode of the semiconductor device, and the second end of the resistor forms the negative electrode of the variable resistance circuit; the gate of the semiconductor device is connected with the cathode of the variable resistance circuit; the positive electrode of the semiconductor device constitutes the positive electrode of the variable resistance circuit. According to the invention, the variable capacitance diode structure is reconstructed into a three-terminal device and is ingeniously connected with the resistor, the voltage drop generated by the current flowing through the resistor is utilized to automatically adjust the grid bias voltage, and a carrier accumulation layer is formed under the grid, so that the on-resistance is changed; according to the self-adaptive variable resistor, an external control port is not needed, the resistance value can be automatically adjusted according to the voltage at the two ends, the increase amplitude of the current along with the voltage is effectively limited, the circuit structure is simplified, and the manufacturing cost is reduced.

The application provides a high-power PIN limiter, which adopts a three-stage limiting structure, and all the three-stage limiting structures adopt a diode string in reverse parallel connection; four groups of three diodes in series and in reverse parallel connection are adopted in the first stage, so that the high-power resistance of the limiter can be obviously improved, and the I layer thickness of the PIN tube in the first stage is the thickest, so that the limiter has higher resistance power. The microstrip line is combined with the PIN tube in reverse parallel connection, so that the L-band high-power limiter with excellent comprehensive performance is realized.

The invention discloses a control method and system for an L-band amplitude limiter, and relates to the technical field of control methods, a plurality of amplitude limiting characteristics are determined based on the identification of multi-modal data, and the amplitude limiting mode of the L-band amplitude limiter is determined according to the plurality of amplitude limiting characteristics and the model and use scene of the L-band amplitude limiter. And the accuracy of the amplitude limiting mode of the L-band amplitude limiter is improved. Therefore, the amplitude limiting range of the L-band amplitude limiter is determined based on the current working data of each electronic component and the current working data of the L-band amplitude limiter, and a main amplitude limiting path and a secondary amplitude limiting path are determined according to the amplitude limiting range, the amplitude limiting mode and the corresponding working path of the L-band amplitude limiter; the working efficiency of the L-band amplitude limiter is determined based on the current working data of the L-band amplitude limiter, and the amplitude limiting control level of the L-band amplitude limiter is determined according to the working efficiency of the L-band amplitude limiter, the main amplitude limiting path and the secondary amplitude limiting path, so that the accuracy of the amplitude limiting control level of the L-band amplitude limiter is improved.

The present disclosure provides a limiter, comprising at least two cascaded limiting circuits and a matching network, the matching network is connected to two adjacent cascaded limiting circuits respectively, and the matching network is composed of impedance matching elements; by selecting the matching form and quantity of the impedance matching elements and adjusting the matching value of the impedance matching elements, the working frequency band of the limiter can be adjusted, so that the limiter can be applied to a conventional communication frequency band; the matching network formed by the impedance matching elements has a small volume and can be applied to a terminal device, can meet the miniaturization requirement of the terminal device, and the volume is reduced, more diodes can be arranged in the limited space, so that the power capacity of the limiter is improved. The present disclosure also provides an electronic device.