9results about "One-port active networks" patented technology

An impedance circuit includes a first poly-resistor and a second poly-resistor. The first poly-resistor has a first terminal coupled to a first node, and a second terminal coupled to a second node. The second poly-resistor has a first terminal coupled to the first node, and a second terminal coupled to the second node. The resistance between the first terminal and the second terminal of the first poly-resistor is determined according to a first control voltage. The resistance between the first terminal and the second terminal of the second poly-resistor is determined according to a second control voltage. The first control voltage and the second control voltage are determined according to a first voltage at the first node and a second voltage at the second node.

This application provides a signal processing circuit and an electronic device. The signal processing circuit includes: a charge amplifier circuit for receiving a differential charge signal output from a sensor; amplifying and converting the differential charge signal to output a first voltage signal; a non-inverting amplifier circuit connected to the charge amplifier circuit for receiving the first voltage signal; amplifying the first voltage signal to output a second voltage signal; a voltage-controlled filter circuit connected to the non-inverting amplifier circuit for receiving the second voltage signal; amplifying and filtering the second voltage signal to output a third voltage signal; and a hysteresis comparator circuit connected to the voltage-controlled filter circuit for receiving the third voltage signal and comparing it to obtain a stable square wave signal. The solution provided in this application can effectively suppress common-mode noise signals, has a fast response speed, is less affected by circuit impedance, and produces a better square wave signal output.

To obtain desired voltage-capacity characteristics by adding a peripheral circuit even in a case where a variable capacitance element with a small capacity variable ratio is used.SOLUTION: An electronic circuit comprises: a DC voltage source; a first variable capacitance element whose cathode is connected with the DC voltage source via a first resistor and whose anode is grounded; a second variable capacitance element whose cathode is connected with the DC voltage source via the first resistor and a second resistor and whose anode is grounded; and a transistor whose gate is applied with a predetermined voltage, whose drain is connected with a connection point between the first resistor and the second resistor, and whose source is connected with a connection point between the second resistor and the second variable capacitance element.SELECTED DRAWING: Figure 5

The utility model discloses a numerical control frequency modulation filter and a voltage converter. Wherein the voltage converter comprises field effect transistors Q1 and Q2, diodes D1 and D2, resistors R1, R2 and R3 and an inductor L23; one end of the resistor R3 is connected with the grid electrode of the field effect transistor Q2, and the source electrode of the field effect transistor Q2 is connected with a power supply; the diode D2 is connected with the inductor L23 in parallel, one end of the parallel connection is connected with the drain electrode of the field effect transistor Q2 and the grid electrode of the field effect transistor Q1, and the other end of the parallel connection is connected with the cathode of the diode D1; after the resistor R2 and the resistor R1 are connected in series, the resistor R2 is connected with the drain electrode of the field effect transistor Q2, and the resistor R1 is connected with the drain electrode of the field effect transistor Q1; the source electrode of the field effect transistor Q1 is connected with the anode of the diode D1; and a power supply is connected between the connecting lines of the resistor R2 and the resistor R1. According to the ultra-high-speed switching circuit of the utility model, the principle that the inductor can hinder sudden change of current is utilized, the gate-source voltage of the field-effect transistor is rapidly increased, and the field-effect transistor is rapidly conducted, so that the frequency hopping speed of the high-power frequency hopping filter reaches within 10us.

Embodiments of the present disclosure provide a filter, an integrated passive device, an electronic device, and a display apparatus. The filter is applied in the field of radio frequency and includes: a first port, a second port, a first band-stop filter circuit, a low-pass filter circuit, a band-pass filter circuit, and a high-pass filter circuit. The first band-stop filter circuit is coupled to the first port, and is configured to perform out-of-band suppression on a signal input from the first port and input a signal subjected to the out-of-band suppression to the low-pass filter circuit. The low-pass filter circuit is configured to input a first signal, a frequency of which is between a first frequency and a second frequency, of the signal input by the first band-stop filter circuit to the band-pass filter circuit.

The utility model discloses a filter suitable for a high-altitude low-pressure environment, which comprises a resonant cavity, a radio frequency resonant circuit is arranged in the resonant cavity, pouring sealant is filled in the resonant cavity, and the pouring sealant at least completely submerges the radio frequency resonant circuit in the resonant cavity; wherein the radio frequency resonant circuit comprises a resonant inductor, a diode and a resonant capacitor; one end of the resonant inductor is welded on the wall of the resonant cavity and is a short-circuit end, and the other end of the resonant inductor is connected with the cathode of the diode and the resonant capacitor; and the anode of the diode is welded on the structural wall of the resonant cavity. According to the utility model, the internal gap of the frequency hopping filter is filled with the pouring sealant, and the pouring sealant replaces air to serve as an insulating medium in a high-altitude low-pressure environment, so that the possibility of sparking of the high-power frequency hopping filter in a full-power state is avoided.

The invention discloses a controllable resistor module linearly changing along with current and application of the controllable resistor module. A controllable resistor comprises an operational transconductance amplifier, a PMOS (P-channel Metal Oxide Semiconductor) tube PM1 and a PMOS tube PM2, the controllable resistor module can generate an equivalent resistor in direct proportion to a sampling current, so that the equivalent controllable resistor Rds and the Isense can be linearly correlated, the influence of process errors and temperature is small, the generated error is small, and the controllable resistor module can be applied to current-controlled oscillators, automatic gain control and other scenes needing controllable resistors.

Provided is a digital variable reactance element that has a wide variable width. A digital variable reactance element 1 comprises a plurality of digital capacitors 2 and a plurality of digital inductors 4. The plurality of digital capacitors 2 and the plurality of digital inductors 4 are connected in series or in parallel. Each of the plurality of digital capacitors 2 has a capacitor C1 and a first digital switch Q that are connected in series or in parallel, and the first digital switch Q can be switched between two states, which are an on-state and an off-state. Each of the plurality of digital inductors 4 has an inductor L1 and a second digital switch Q that are connected in series or in parallel, and the second digital switch Q can be switched between two states, which are an on-state and an off-state.