Thyristor switching circuit for a pulsed control system of dc electric motors
Calculated surges in switching circuit of pulsed control system direct current electric motor
Veitsman, L. YU.↗
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A sweep algorithm for massively parallel simulation of circuit-switched networks
A new massively parallel algorithm is presented for simulating large asymmetric circuit-switched networks, controlled by a randomized-routing policy that includes trunk-reservation. A single instruction multiple data (SIMD) implementation is described, and corresponding experiments on a 16384 processor MasPar parallel computer are reported. A multiple instruction multiple data (MIMD) implementation is also described, and corresponding experiments on an Intel IPSC/860 parallel computer, using 16 processors, are reported. By exploiting parallelism, our algorithm increases the possible execution rate of such complex simulations by as much as an order of magnitude.
Gaujal, Bruno↗
Computer program detects transient malfunctions in switching circuits
A program which accepts a system model in the form of Boolean equations and solves these equations using a ternary algebra will determine the response of large combinational and sequencial switching circuits to given input changes, taking into account malfunctions due to races, hazards, and oscillations.
Calvin, E. L.↗
Low cost switching circuit for van der Pauw resistivity and Hall measurements at various temperatures
The electrical characterization of materials, particularly superconductors, semiconductors, and those undergoing metal-insulator transitions (MITs), relies significantly on resistivity and Hall measurements as a function of temperature. The van der Pauw four-point probe method is commonly used for such measurements, which involves resistance measurements for different circuit configurations connected to sample contacts. However, repeating these measurements at different temperatures is challenging and time consuming. Here, this study introduces a novel approach utilizing a switching circuit controlled by an Arduino device and a LabVIEW program to automate resistance measurements for different electrical configurations. The effectiveness of this setup was demonstrated by testing V 2 O 3 thin film samples deposited on Al 2 O 3 (001) substrates using DC magnetron sputtering. The MIT temperature of the sample was 115 K during heating and 100 K during cooling. The sample exhibited p-type charge carriers with a Hall coefficient of 1.3 ± 0.1 x 10 -4 cm 3 /C and Hall mobility of 1.7 x 10 -1 cm 2 /V∙s, which is consistent with findings from other studies employing commercial equipment.
36 MATERIALS SCIENCE↗
Wide bandgap optical switch circuit breaker
A high-voltage switch is adapted for use as a medium-voltage direct current circuit breaker, which provides a low-cost, small-footprint device to mitigate system faults. In one example, a method for operating a wideband optical device includes illuminating the wide bandgap optical device with a light within a first range of wavelengths and a first average intensity, allowing a current to propagate therethrough without substantial absorption of the current, illuminating the wide bandgap optical device with light within the first range of wavelengths and a second average intensity that is lower than the first average intensity to allow a sustained current flow though the wide bandgap optical device, and illuminating the wide bandgap optical device with light within a second range of wavelengths to stop or substantially restrict propagation of the current through the wide gap material.
Voss, Lars F.↗
DC static switch circuit with power saving feature
A main switch transistor is provided with a base drive circuit to vary the base drive current in accordance with load current to minimize power dissipation. Base drive may also be limited to a maximum for overload current limiting.
Baker, Donal E.↗
Electronic switching circuit uses complementary non-linear components
Inherent switching properties of saturable inductors and storage diodes are combined to perform large variety of electronic functions, such as pulse shaping, gating, and multiplexing. Passive elements replace active switching devices in generation of complex waveforms.
Zucker, O. S.↗
Circuit switches latching relay in response to signals of different polarity
A circuit using one power supply and two storage capacitors, which may be separately discharged in opposite directions through a relay in response to change in polarity of a signal, is described.
Smith, L. S.↗
Ring counter circuit switches multiphase motor direction of rotation
Solid state three-phase counter circuit reverses the direction of rotation of a multiphase motor without changing the phase wiring of the supply current source.
Fairbanks, A. F.↗
Wide bandgap optical switch circuit breaker for controlling propagation of current therethrough a wide bandgap optical device
A high-voltage switch is adapted for use as a medium-voltage direct current circuit breaker, which provides a low-cost, small-footprint device to mitigate system faults. In one example, a method for operating a wideband optical device includes illuminating the wide bandgap optical device with a light within a first range of wavelengths and a first average intensity, allowing a current to propagate therethrough without substantial absorption of the current, illuminating the wide bandgap optical device with light within the first range of wavelengths and a second average intensity that is lower than the first average intensity to allow a sustained current flow though the wide bandgap optical device, and illuminating the wide bandgap optical device with light within a second range of wavelengths to stop or substantially restrict propagation of the current through the wide gap material.
Voss, Lars F.↗
MOSFET Switching Circuit Protects Shape Memory Alloy Actuators
A small-footprint, full surface-mount-component printed circuit board employs MOSFET (metal-oxide-semiconductor field-effect transistor) power switches to switch high currents from any input power supply from 3 to 30 V. High-force shape memory alloy (SMA) actuators generally require high current (up to 9 A at 28 V) to actuate. SMA wires (the driving element of the actuators) can be quickly overheated if power is not removed at the end of stroke, which can damage the wires. The new analog driver prevents overheating of the SMA wires in an actuator by momentarily removing power when the end limit switch is closed, thereby allowing complex control schemes to be adopted without concern for overheating. Either an integral pushbutton or microprocessor-controlled gate or control line inputs switch current to the actuator until the end switch line goes from logic high to logic low state. Power is then momentarily removed (switched off by the MOSFET). The analog driver is suited to use with nearly any SMA actuator.
Gummin, Mark A.↗
Switching Circuit Regulates Solenoid Current
New circuit requires no heat sink and is compact. Parts cost no more than those of linear regulator. Switching regulator repeatedly causes solenoid current to build up to maximum level, then to decay to minimum level: thus current ripples about commanded intermediate level. FET's dissipate significant amounts of power only during brief turn-on and turn-off intervals.
Simon, Richard A.↗
Open Circuit Switch Fault Management Method of a Multi-Phase Synchronous Buck Converter for EV Charging Application
Multi-phase synchronous buck converter (MSBC) is becoming popular for the electric vehicle (EV) charging application because of its higher efficiency, smaller passive component sizes, bidirectional power flow, and output current ripple reduction through interleaving. This converter also provides higher reliability than the traditional single phase converter since its modular structure enables fault tolerant operation. Fault management in the converter requires the detection of switch fault, shut down of the faulty phase, and reconfiguration of the PWM signals for the healthy phases to avoid circulating current and high output current ripple. In addition, it is desirable that the fault management method can be implemented using the micro-controller unit (MCU) or digital signal processor (DSP), which are widely used to control power converters. This paper presents a fault management method for detecting switch faults and reconfiguring healthy phases using a DSP. The method is validated through simulations and experiments using a commercial off-the-shelf power stack.
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
Variable-pulse switching circuit accurately controls solenoid-valve actuations
Solid state circuit generating adjustable square wave pulses of sufficient power operates a 28 volt dc solenoid valve at precise time intervals. This circuit is used for precise time control of fluid flow in combustion experiments.
Gillett, J. D.↗
Switching circuits with fast response and low power drain
New logic circuits have response times no longer than 10 nanoseconds and drain only milliwatts of power. The family includes AND and NAND gates and forms the basis of all logic functions. The basic circuits are used in various types of digital-data-processing systems.
Cancro, C. A.↗
Novel shift register eliminates logic gates and power switching circuits
Register requiring two integrated circuits per stage has nominal power dissipation of 3.5 mW per stage, its use eliminates reset pulse, allowing data transfer to occur in less than 1 microsecond, and eliminates power application to both right and left portions of the register simultaneously.
Cliff, R. A.↗
A switching circuit for a low voltage, medium current dc power supply.
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Luke, K.↗