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.↗
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.↗
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.↗
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.
Explore the source record for details and available documents.
Luke, K.↗
Solid state zero-bias bilateral switch
Circuit switches a plus or minus 2.5 volt peak, dc to 300 kHz input to an operational amplifier. Featured is a bilateral transistor which draws a saturation current of equal amplitude and opposite polarity to the saturation current of the bilateral transistor, cancelling the dc bias effect at the output.
Husted, J. M.↗
Solid state remote circuit selector switch
Remote switching circuit utilizes voltage logic to switch on desired circuit. Circuit controls rotating multi-range pressure transducers in jet engine testing and can be used in coded remote circuit activator where sequence of switching has to occur in defined length of time to prevent false or undesired circuit activation.
Peterson, V. S.↗
Simple circuit reduces transistor switching time
Silicon-Controlled Rectifier /SCR/, gated by a voltage divider, controls the potentiometer in transistorized switching circuits. The SCR acts as a gate to trigger the switching transistor only when the input signal reaches an amplitude that will switch the transistor rapidly.
Source record↗
Remote Power Controllers For High-Power dc Switching
Circuits combine functions of remotely controlled switch and circuit breaker. Circuits developed at different power levels but conceptually very similar. Selection of appropriate switching devices and minor modifications, circuits used to build RPC's covering range of voltage and power levels limited only by switching devices chosen. RPC's using GTO's have power capability ranging from 7.8 to 52 kW, while those using MOSFET's range from 8 to 15 kW. Applications include satellite, Space Station, commerical aircraft, naval vessels, and numerous industrial areas.
Sturman, J. C.↗