375 results about "Multivibrator" patented technology

The non-volatile memory cell has a volatile memory means for storing an item of binary information. Furthermore, the memory cell comprises only a single programmable resistance element for non-volatile saving of the stored information and a means for saving the information in the resistance element. A means for retrieving the saved information is additionally present.

An LC-VCO includes a multivibrator which outputs a frequency signal, a fine tuning circuit which tunes the frequency signal by a first amount, a coarse tuning circuit which tunes the frequency signal by a second amount, and a control circuit which controls the fine and coarse tuning circuits. The coarse tuning circuit is formed from one or more capacitive arrays and the fine tuning circuit is formed from one or more varactors. The capacitive arrays are preferably controlled by a digital signal, where each bit selectively couples a respective capacitor to the multivibrator. An analog signal controls the value of the varactors. The capacitive arrays and varactors charge and discharge an inducator in the multivibrator to tune the frequency signal. The VCO may be incorporated within a phase-locked loop, where the capacitors may be assigned different weight and / or redundancy values to tune an output frequency signal. In one embodiment, coarse tuning and lead-lag detection is performed more accurately to allow the size of the varactors to become significantly reduced compared with other circuits which have been proposed.

A direct-current residual-current detecting device, driven by a monopolar power supply, comprises: a power conversion self-balancing circuit (102), a residual-current transformer (106), and a comparator (108). An input end of the power conversion self-balancing circuit (102) is connected to the monopolar power supply, the power conversion self-balancing circuit (102) converts monopolar power into bipolar power and outputs the bipolar power, and the power conversion self-balancing circuit (102) supplies power to another component. The residual-current transformer (106) is provided with an RL multivibrator, a square wave pulse voltage drive circuit (104) circularly exerts positive and negative direction voltages to a secondary winding of the residual-current transformer (106), and the residual-current transformer (106) outputs a corresponding sampling voltage. The comparator (108) obtains the sampling voltage output by the residual-current transformer (106), compares the sampling voltage with a voltage threshold of the comparator, and generates a positive and negative alternately square wave signal, the square signal is fed back as output of the comparator (108) to the square wave pulse voltage drive circuit (104) as a drive signal, and output of the comparator (108) is further used as output of the direct-current residual-current detecting device to represent the polarity and size of a direct-current residual-current.

A logic built-in self test (LBIST) system comprises a device under test having a first plurality of first bistable multivibrator circuits an LBIST controller, and a second plurality of second bistable multivibrator circuits. Each second bistable multivibrator circuit is coupled to a corresponding first bistable multivibrator circuit to swap a second state value kept by the second bistable multivibrator circuit with a first state value kept by the corresponding first bistable multivibrator circuit depending on a first control signal from the LBIST controller and the second bistable multivibrator circuits are coupled to form one or more scan chains when receiving a second control signal from the LBIST controller.

The control card consists of control unit, switching value input unit and signal output unit. The control unit includes RS-232, quartz multivibrator, circuit for monitoring power supply; switching value input unit includes acquisition module and isolation shaping module; signal output unit includes current signal output unit and direction signal output unit. 8254 programmable chip is adopted in pulse control circuit for counting and timer. X5045 is utilized in EEPROM chip. Features of the card are: simple hardware structure, few number of pins, and no need of driving program.

The present invention relates to an average current controller, an average current control method and a buck converter using the average current controller. The average current controller includes a first comparator for generating a high H signal, a multivibrator for generating a TAVG pulse signal by receiving a high H signal outputted from the first comparator, a timing generator for generating a signal CH_ON to charge / discharge a capacitor by using at least the TAVG pulse signal, an integrator circuit unit for charging / discharging the capacitor, a second comparator for outputting a corresponding signal, an up / down counter for increasing or decreasing a counting value and a digital / analog converter for outputting by converting an output (digital signal) of the up / down counter into an analog signal.

The continuous-level memristor emulator is a circuit that uses off-the-shelf components to emulate a memristor. The circuit uses two current-feedback operational-amplifiers (CFOAs) and uses an operational transconductance amplifier (OTA)-based circuit in place of a diode resistive network to provide a continuous level of memristance instead of two binary states. The OTA is forced to work in its nonlinear region by the voltage VDC applied to its positive input terminal. Thus, the transfer function of the OTA-based circuit will be a nonlinear function. Experimental testing shows that the continuous-level memristor emulator is operational as a memristor, and the emulator may be used, e.g., in place of a memristor in a multivibrator circuit.

A leaf blower with a lithium battery multivibrator superposition voltage unit circuit multi-tube noise elimination function comprises a battery state display unit. Four LEDs serve as display devices,through state combination, the voltage, the electric quantity and the temperature of a battery and whether the battery is abnormal or not can be correctly displayed, and therefore the working state ofthe battery can be judged. The charging voltage supplied to the lithium battery is not traditional constant-voltage constant-current direct current charging voltage but the multivibrator superposition voltage, formed by mixing the rectified voltage of a lithium battery charging circuit with the pulse voltage led from a free running multivibrator originally used for an electric discharge machiningmachine tool, generated by a multivibrator superposition voltage unit circuit, and the lithium battery is charged through holes, storing electric charges, in the lithium battery in a multi-point acupuncturing mode. The mean value of the pulse voltage led from the free running multivibrator is 82 V, the pulse frequency of the pulse voltage is 82 kHz, and twice the result can be obtained with halfthe effort.

A DC-to-DC converter is provided with an astable multivibrator containing a first time constant circuit for setting an ON period of an output and a second time constant circuit for setting an OFF period of the output, and provided with a switching element controlled by the output. The output voltage is controlled by changing the duty ratio of the astable multivibrator in accordance with the output voltage.

The invention relates to a multi-core cable wire testing device, aiming to solve the problems of low efficiency, easy errors, hardly discovery of poor contact caused by faulty welding between a wire and a terminal, and the like in the prior art. The multi-core cable wire testing device comprises a testing instrument and a vibrator, wherein the testing instrument comprises an operation panel and a testing circuit which is formed by sequentially connecting a multivibrator, a frequency division loop, a sequential output loop and a display loop in series, a power supply supplies power to the multivibrator and the loops, and two testing sockets are respectively connected with the sequential output loop and the display loop. The invention detects a multi-core cable wire under the vibration condition, can not only detect the wiring correction, but also detect whether hidden danger, such as poor contact due to faulty welding, and the like exists.

An arc fault circuit interrupter (AFCI) device prevents malfunction of an electric circuit and checks the state of the circuit and connection state of lines. One of a phase conductor line and a neutral conductor line is wound around a transformer which converts a current difference flowing in the AC line into voltage to detect 1a whether an arc fault occurs, and a voltage induced by the wound line is rectified into direct-current and is converted into constant voltage to obtain power for the AFCI. An arc wave generator includes a rectifier to generate a rectified signal; a drop resistor which drops the voltage of the rectified signal to generate a voltage-dropped signal; and a mono-stable multivibrator which adjusts a voltage level and a pulse width of the voltage-dropped signal and generates a pulse signal that is used to generate a false arc for testing the AFCI.

An acceleration sensor outputs a signal in accordance with acceleration. A differentiator outputs a differential signal of the output signal. A comparator inverts the state of an output when the differential signal goes beyond a threshold. A monostable multivibrator maintains the state-inverted signal of the output for a predetermined period of time. An integrator integrates the acceleration detection signal. A comparator inverts the state of an output signal when an integrated signal goes beyond a threshold. A fall determination processor outputs a signal out indicating that a fall has been detected in a situation in which, when the output of the monostable multivibrator is active, the state of the output of the comparator is inverted.

For the electrically isolated transmission of digital signals, an isolating path of a channel formed by a transformer is used. The channel further includes a conversion stage for converting the digital signal to a transmissible coupling signal and a conversion stage for converting a coupling signal to the digital signal. This conversion is accomplished by a monostable multivibrator. The coupling signal is a square-wave voltage which is generated by a delay circuit in the conversion stage and is converted on the isolating path to a square-wave voltage serving as the coupling signal.

The invention provides a starting circuit for a relay protection switching value output circuit. The starting circuit can reliably protect a relay protection device from sending outlet instructions by mistake. According to the technical scheme of the starting circuit, a GPIO pin of a processor and an IO pin of a programmable device are connected with an input pin of a single stable-state multivibrator, an output pin of the multivibrator controls on-off of an optocoupler, a relay is controlled to start and be locked through on-off of the optocoupler, and the relay starts and is locked to control a power supply of a switching value output relay. On the condition, switching value output instructions are sent out normally only when the processor is completely initialized and complete operation, the programmable device completes configuration completely, a system operates normally, and the power supply of the switching value output circuit is turned on. If processing failures, or operation system abnormality or programmable device failures occur, the power supply of the switching value output circuit is cut off, the protection device can not send out switching value output instructions, so that risks, of sending switching value output instructions by mistake, caused by failures of the relay protection device are reduced.

The present invention provides a constant gm circuit that generates a bias current for a emitter / source-coupled multivibrator oscillator. The stable gm bias limits the temperature dependence of the oscillator. Trimming a resistor in the constant gm circuit compensates for process variations, and current sources may be provided that are mirrors of the bias current that are also substantially independent of the supply voltage. The present invention provides an oscillator with less that 1% frequency changes due to PVT variations.

A DC-to-DC converter is provided with an astable multivibrator containing a first time constant circuit for setting an ON period of an output and a second time constant circuit for setting an OFF period of the output, and provided with a switching element controlled by the output. The output voltage is controlled by changing the duty ratio of the astable multivibrator in accordance with the output voltage.

A digital motor control system utilizes at least two variable pulse generators to produce two streams of pulse width modulated pulses to control the motor speed and direction of rotation of a motor. An input control signal may be compared with two reference signals, such as two waveforms which are inverted with respect to each other, to produce two streams of pulse width modulated signals. A logic circuit combines the two streams of pulses. In one embodiment, depending on the input control signal level, where the two streams do not overlap, reverse motor control signals are produced and where the two streams overlap, forward motor control signals are produced. As the pulse widths of the pulse width modulated pulses change, the motor may receive continuous power in one direction, slow down, stop, and then increase speed in the opposite direction until it receives continuous power in the other direction. The variable pulse generators may be of various types including one-shot multivibrators and comparators. In one embodiment, two sets of N-channel and P-channel power switches may be utilized to drive the motor.

The invention discloses a metal detector. The metal detector comprise a coil oscillation circuit and a control circuit; the coil oscillation circuit comprises a multivibrator, a first amplification circuit and a detection coil which are connected in order; the control circuit comprises a single-chip microcomputer, the single-chip microcomputer is connected with a display module, a power supply module, an A / D conversion module and an alarm circuit in order, the A / D conversion module is connected with a peak detection module, a second amplification circuit and a Hall element in order, and the Hall element is connected with the detection coil. The metal detector solves the problem of low detection precision in prior art.

The invention relates to a control circuit of a bionic synchronous signal lamp, which is connected with an LED light source group and comprises a synchronous signal control module and an LED driving module, wherein the synchronous signal control module comprises a synchronous signal generating module used for generating and transmitting an infrared synchronous signal, a synchronous signal receiving module used for receiving the infrared synchronous signal, a multivibrator circuit which is used for generating a PWM signal and adjusting the PWM signal according to the infrared synchronous signal; the PWM signal controls the LED driving module to supply power for the LED light source group in an intermittent way; and the synchronous signal generating module generates and transmits the infrared synchronous signal when the LED light source group lightens. The invention also relates to the bionic synchronous signal lamp which does not need a synchronous cable and other accessory equipment such as a centralized-control box and the like; the number of the bionic synchronous signal lamps is not limited; and the bionic synchronous signal lamp has better fault tolerance, no electromagnetic radiation pollution, low cost and flexible installation.

The invention discloses a multi-path adjustable self-excited multivibrator. Under the condition that an external trigger signal does not exist, the multivibrator can continuously, periodically and automatically generate rectangular pulses and can be set according to different required frequencies, different width ratios and the number of controllable paths. The type of circuit can be widely applied in various living fields. The circuit is a symmetric multi-path adjustable self-excited multivibrator consisting of a triode, a capacitor and a waveband switch serving as a core element. The circuit does not have a stable state; switch on and switch off of the triode are controlled by charging and discharging of the capacitor; and the circuit automatically excites between two transient states.

The invention discloses a proximity transducer that includes multivibrator and probe. One end of any capacitance of the multivibrator connects to metal probe. When powering on, the multivibrator would charge or discharge capacitance to generate low frequency vibration. The altering current would radiate low frequency electromagnetic wave. Any object closing the probe would adsorb the electromagnetic wave that could influence the quantity of electric charge of the probe to generate micro alteration of vibration frequency to testing the material, volume and shape parameter. The invention has little pollution to the environment and the probe area could be designed in random shape. When probe connects or gets close to metal or conductive object, the probing range would be extended.

The invention discloses a DC-DC conversion circuit suitable for power supply on a high-voltage side of an IGBT drive module. The circuit comprises a power supply for supplying work voltage, an unsteady-state multivibrator, a control pulse waveshaping circuit, an LC resonance circuit, a high-frequency pulse transformer, a high-voltage side waveshaping filter circuit, a second-level voltage-stabilizing circuit, an output voltage impedance regulation and current amplifying circuit, a seventh diode D7 and an eighth diode D8, wherein the seventh diode D7 and the eighth diode D8 are used for controlling safety power-on time intervals between a first field effect tube Q1 and a second field effect tube Q2 and preventing the situation that the first field effect tube Q1 and the second field effect tube Q2 are simultaneously powered on and accordingly a power supply of a low-voltage side is short-circuited. The invention further comprises a current-limiting circuit which can connect the power supply before current limiting to the drive module needing to provide powerful enough current output capacity for an IGBT and connect the power supply after current limiting to other control units on the high-voltage side of the IGBT drive module. The DC-DC conversion circuit is perfect in function, reliable in performance, convenient to use and easy to popularize and use.

The invention discloses a combustible gas and smog leakage reminding device. The combustible gas and smog leakage reminding device is characterized by comprising a 9V direct-current electrical source, a gas detection circuit, a critical value sampling circuit, an astable multivibrator circuit and an audio output circuit. The gas detection circuit is composed of a gas sensor QM and a resistor R1, and the selected model of the gas sensor QM is QM-N6. The astable multivibrator circuit and the audio output circuit are composed of a time-base circuit IC1, a resistor R2, a resistor R3, a capacitor C1 and a piezoelectric ceramic piece HA, and the selected model of the time-base circuit IC1 is NE555. The combustible gas and smog leakage reminding device is a gas leakage warning device with the gas sensor used as a detecting element, the device is suitable for detecting leakage of volatile gas such as natural gas, coal gas, gasoline, carbon monoxide, hydrogen, alkanes and alcohol, and timely detection warning can be conducted on smog formed by fires of wood, paper, woolens, rubber products, plastic products and the like.

The invention relates to a human body safety socket which comprises a socket body and is characterized by also comprising an AC (alternating current) branch detection circuit for monitoring load or electric leakage of the socket, a current detection transformer for detecting the current of the socket, an electric leakage detection coil and an impedance pre-detection circuit adopting a multivibrator, which are respectively connected with a central function controller through an amplifying, rectifying and shaping circuit, wherein the current detection transformer and the electric leakage detection coil are used for detecting the current of the socket; the central function controller is connected with a first relay responsible for the on / off of test ends of the AC current branch detection circuit, the current detection transformer and the electric leakage detection coil and a second relay responsible for conversion work of connecting a mains supply to the socket. According to the invention, no electric shock of people can be realized through the bare socket, a user is ensured to find out the power capacity of the site to the electrical appliances or the electrical appliances in failure as soon as possible; and moreover, the user does not need to perform switching-on operation in case of emergency, and just needs to withdraw the electrical appliances, so that the circuit can return to the condition that the idle socket does not carry the strong current, and the human body safety socket has better practical value.

The invention relates to a diode reverse recovery characteristic tester. The diode reverse recovery characteristic tester is provided with a power source, an inductor and a driving device. The power source, the inductor, an inductive load and the driving device are connected together in series, and after an element to be tested is connected with a current transformer in series, the element to be tested is connected with the inductive load in parallel. The driving device is provided with a first wiring terminal, a second wiring terminal and a third wiring terminal. The first wiring terminal is connected with the inductive load, the second wiring terminal is connected with the power source, and a gate resistor and a multivibrator are connected between the third wiring terminal and the second wiring terminal in series. The diode reverse recovery characteristic tester can be freely adjusted according to specific test requirements, the reverse recovery time and other reverse recovery characteristics of a diode can be tested, and both an ordinary diode and any device comprising a diode can be tested; the diode reverse recovery characteristic tester is wide in test range, high in precision and wide in test voltage range, and the actual characteristics of various reverse recovery characteristics of a diode can be analyzed clearly and accurately by an external oscilloscope.