72 results about "Voltage controlled resistor" patented technology

An oscillator produces an oscillator output signal usable as a clock signal, otherwise as a frequency reference on an integrated circuit. The oscillator includes an RC network with a voltage-controlled element, such as a voltage-controlled resistor, voltage-controlled capacitor or a combination including a voltage-controlled resistor and voltage-controlled capacitor. Also, a tunable element having an adjustable resistance determined by a first static parameter is included in the RC network. The oscillator also includes a feedback circuit which can include a frequency-to-voltage converter. The feedback circuit generates a control signal for the voltage-controlled element. The feedback circuit includes a feedback reference circuit having a reference output determined by a second static parameter, and a loop amplifier responsive to the reference output and the oscillator output signal.

The present invention provides one kind of surge current preventing and time sequence controlling device and method for plug-and-play electronic equipment. The device includes voltage controlled resistance unit connected serially to the power source input end of the electronic equipment; and controller with control end connected to the control end of the voltage controlled resistance unit to control the equivalent resistance, which is controlled to be relatively great while the electronic equipment is accessed to the power source and relatively small after preset time. The controller includes resistor and capacitor and controls the control voltage of the control end via controlling the charge and discharge of the capacitor. The method includes the following steps: determining the sequence of applying different power voltages to the electronic equipment; judging the plugging of electronic equipment; and lowering the limiting resistances serially connected to the input power sources in the sequence.

The invention discloses an annular high-speed voltage-controlled oscillator. The annular high-speed voltage-controlled oscillator is formed by series connection of four levels of delay units, wherein the negative output end (Vout-) of each level of delay unit is connected with the positive input end (Vin+) of a corresponding next level of delay unit, the positive output end (Vout+) of each level of delay unit is connected with the negative input end (Vin-) of a corresponding next level of delay unit, the negative output end (Vout-) of the last level of delay unit is connected with the negative input end (Vin-) of the first level of delay unit, and the positive output end (Vout+) the last level of delay unit is connected with the positive input end (Vin+) of the first level of delay unit. According to the annular high-speed voltage-controlled oscillator, an active electrical inductance structure is additionally arranged based on traditional delay units, a pair of PMOS tubes with grid electrodes connected to the ground are additionally arranged at a load end, therefore, oscillation of a circuit within the whole voltage range is guaranteed, extra electric currents can be provided for the circuit, and the oscillation frequency is improved; a control voltage is connected to the grid electrodes of the pair of PMOS tubes so that the frequency of the delay units can be controlled, and the PMOS tubes serve as voltage-controlled resistors and are used for adjusting the oscillating frequency.

The invention relates to a multifunctional internal combustion arc welding generator. The generator comprises an internal combustion engine, a generator rotor, a trigger circuit, a silicon controlled rectifier switch, a three-phase bridge rectifier, an auxiliary power supply rectifier circuit, an excitation current adjusting circuit, a generator stator, a first switch tube T1, a second diode D2, a first capacitor C1, a first diode D1 and a chopping main loop. The invention provides a structure of a voltage controlled resistor and a control mode aiming at the problem of difficulty in parallel current sharing of a chopping switch tube; the controlled resistor is controlled by an outer ring negative feedback control loop consisting of a photoelectric coupler, an outer ring control circuit, an outer ring given circuit, an outer ring hall current sensor and a voltage sampling circuit; a constant current, constant current and out-pulling and flat hard external characteristic curve is outputby selecting and switching a feedback signal output by the outer ring hall current sensor and the voltage sampling circuit; thus the requirements of argon arc welding, low-hydrogen electrode manual arc welding and cellulose electrode vertical down welding on the external characteristic curve and the welding process performance of a welding machine are met.

A current regulating apparatus capable of regulating an electrical current with a high level of precision and over a wide range of voltages includes a first depletion mode field-effect transistor (FET), a second depletion mode FET, and a fixed resistor. The second depletion mode FET and fixed resistor are connected in series and across the gate-source terminals of the first depletion mode FET. The first depletion mode FET operates as an adjustable current source while the second depletion mode FET is controlled to operate as a voltage controlled resistor. The magnitude of current regulated by the current regulating apparatus is determined based on both the resistance of the fixed resistor and a current-setting control voltage applied to the gate of the second depletion mode FET. Various precision values of regulated current can be realized by simply changing the current-setting control voltage.

The present invention discloses a limiting oscillation circuit. (110) for generating an oscillation signal; a pulse width modulation circuit (120) for generating a pulse width modulation signal based on the amplitude of the oscillation signal; a low pass filter circuit (130) for generating a pulse width modulation signal, (140) for controlling the voltage-controlled resistance circuit (140) for controlling the voltage-controlled voltage signal based on the control of the DC-controlled voltage signal, and a voltage-controlled voltage signal (140) for controlling the voltage- The resistance value of the voltage-controlled resistance circuit (140) is changed to control the amplitude of the oscillation signal. The limiting oscillation circuit of the embodiment of the present invention can improve the performance of the limiter oscillation circuit.

Voltage-controlled semiconductor structures, voltage-controlled resistors, and manufacturing processes are provided. The semiconductor structure comprises a substrate, a first doped well, and a second doped well. The substrate is doped with a first type of ions. The first doped well is with a second type of ions and is formed in the substrate. The second doped well is with the second type of ions and is formed in the substrate. The first type of ions and the second type of ions are complementary. A resistor is formed between the first doped well and the second doped well. A resistivity of the resistor is controlled by a differential voltage. A resistivity of the resistor relates to a first depth of the first doped well, a second depth of the second doped well, and a distance between the first doped well and the second doped well. The resistivity of the resistor is higher than that of a well resistor formed in a single doped well with the second type of ions.

A gate driving circuit is connected to a main switching element. The gate driving circuit includes a gate resistor. The gate resistor includes a voltage controlled resistor of which a resistance value is able to be continuously changed. A switching power supply device includes a gate driving circuit, a main switching element, and a freewheeling diode connected in reverse parallel to the main switching element.

The invention discloses a voltage-controlled resistor circuit which comprises a resistor R1, a resistor R2, a current transmitter U1 and a multiplier M1. The invention aims to solve the problem that the existing adjustable resistor contains a mechanical structure or the resistance value cannot be continuously changed or the adjustable range of the resistance value is narrow. The electrical characteristics of the ports a and b are equivalent to the resistance characteristics, the change of the resistance value is controlled by the voltage uc(t), only four components need to be used, and the device has the advantages of being simple in structure, convenient to implement, free of mechanical parts, capable of continuously changing the resistance value and large in resistance value adjusting range. The voltage-controlled resistor circuit can be widely applied to various circuit design occasions needing the adjustable resistor (especially a voltage-controlled resistor).

The invention discloses a current fractional order integral control type memristor, which includes a pin a, a pin b, a voltage-controlled resistor UR, a resistor R, a current controlled voltage sourceIU and a voltage fractional integrator A, the voltage-controlled resistor UR includes a voltage control terminal uc and a controlled resistor Ru, A resistance value of a controlled resistor Ru in a voltage controlled resistor UR is controlled by a voltage value of a voltage control terminal uc, the current control voltage source IU comprises a current control terminal i and a voltage source output terminal ui. The voltage value of the voltage source output terminal ui in the current control voltage source IU is controlled by the current value of the current control terminal i. The voltage fractional integrator A comprises a voltage input terminal ui and a voltage output terminal uc. The electrical characteristics of the pins a and b of the current fractional-order integral control memristor are equivalent to those of the pins A and B of the memristor M. The current fractional-order integral control memristor is two pins, which further reduces the complexity and the number of components of the existing current fractional-order integral control memristor. The current fractional-order integral control memristor has the advantages of not requiring one end of the pins to be grounded, flexible variation range of the memristor value, and wide working voltage range.

The invention discloses a new and original voltage variable resistor VVR with input and output ports and a first input and second input for control signals to set the impedance between the input and output ports as desired over a certain range and, thus, to optimize the operation of the VVR from the transmitter device control viewpoint as regards both the linearity and minimum impedance. The invention further discloses a method for controlling a VVR and a cellular radio system terminal.

The invention discloses a silicon carbide Schottky diode-based Spice model and a construction method thereof. The model comprises a voltage-controlled capacitor, a voltage-controlled resistor, a voltage-controlled body resistor, and a contact resistor, wherein the voltage-controlled capacitor is used for indicating the depletion layer capacitance of the silicon carbide Schottky diode; the voltage-controlled resistor is connected with the voltage-controlled capacitor in parallel and used for indicating the depletion layer current of the silicon carbide Schottky diode; the voltage-controlled body resistor is in series connection with parallel connection nodes of the voltage-controlled capacitor and the voltage-controlled resistor, and used for indicating the body resistance of the silicon carbide Schottky diode; the contact resistor is connected with the voltage-controlled body resistor in series. The silicon carbide Schottky diode-based Spice model disclosed by the invention has the advantage that the obtained diode dynamic curve is well matched with the experimental data. The model can be used for evaluating dynamic performance of the diode accurately and also used for guiding design and application of the silicon carbide Schottky diode.

The invention discloses a very simple floating magnetic control memristor circuit simulation model which comprises a port a, a port b, a voltage controlled resistor UR, a resistor R and a voltage integrator A. The voltage controlled resistor UR comprises a voltage control end uc and a controlled resistor Ru; a resistance value of the controllable resistor Ru in the voltage controlled resistor UR is controlled by a voltage value of the voltage control end uc; and the voltage integrator A comprises a voltage input end u and a voltage output end uc. Electrical characteristics of the ports a and bof the floating magnetic control memristor circuit simulation model are equivalent to characteristics of A and B ports of a magnetic control memristor W, only needs to use existing three elements insimulation software, and is a two-port model; complexity and the element number of an existing magnetic control memristor circuit simulation model are further reduced; and the very simple floating magnetic control memristor circuit simulation model has the advantages of flexible memristive value changing range, no grounding limitation, wide working voltage range and easiness for understanding.

The invention discloses a location inputting device using head twisting induction. A fixed part is arranged on a collar on the back or the skin below the neck and connected with a pressure control inducting device like a pressure control capacitor or resistor through a spring. When the head twists horizontally or vertically, pressure control induction signals are generated, namely the capacitance value of the pressure control capacitor or the resistance value of the pressure control resistor is changed, and pressure control induction signals are input into a chip and processed to generate corresponding location signals. The realizing mode of a traditional location inputting device (a mouse) is abandoned, pressure control induction is adopted directly, the circuit system is simpler than the traditional location inputting device (the mouse), the location inputting device is easy to obtain, capable of being integrated with wearable equipment, convenient to carry about and not prone to damage, power consumption can be reduced, the location speed is increased, and the location accuracy is improved.