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Superconductor–semiconductor hybrid circuits can combine the benefits of the high-speed and low-power operation of single-flux quantum circuits and high integration densities of CMOS technology such as memory. The Suzuki stack, a type of Josephson latching driver/amplifier, is a widely used interface circuit in Josephson–CMOS hybrid memories. Due to the limited cooling power at cryogenic temperatures, the power dissipation is becoming an important concern, especially in large-scale systems. An optimization technique to significantly reduce the power dissipation of Suzuki stack circuits is proposed in this article. The proposed design can reduce the power dissipation by 30–70% while causing a voltage drop of 2–9% in the output voltage depending on the circuit parameter configuration. The tradeoffs between the power dissipation and output voltage characteristics are discussed. The proposed design can operate correctly within at least $\pm$ 20% of process parameter variations as demonstrated with extensive simulations. [ABSTRACT FROM AUTHOR]

High-voltage direct current (HVDC) circuit breaker development and deployment strongly depend on the testing process, which ensures that the HVDC circuit breakers will satisfy design requirements. This article presents an HVDC circuit breaker test bench circuit configuration that can provide controllable large output currents to simulate different fault conditions for the current breaking test and high output voltage for the dielectric withstand test. The current breaking test circuit is based on multiple cascaded power converters connected in parallel to provide the necessary output current capability. Each cascaded power converter is composed of multiple cells that are operated by a phase-shifted pulsewidth-modulated signal for greater controllability and higher quality of the output waveform. The dielectric withstand test circuit is a simple high-voltage source with a low power rating that can also be used to charge the test bench and the internal circuitry of the circuit breaker that is to be tested. The proposed test bench ensures that fault conditions can be replicated accurately and offers greater flexibility by being able to test mechanical, semiconductor-based, or hybrid HVDC circuit breakers with different current and voltage ratings on the same hardware without any changes. The idea and the operating principle of the proposed test bench are verified experimentally on a downscaled system that consists of three cascaded power converters connected in parallel with three cells per cascaded power converter and with a total equivalent switching frequency of 92.5 kHz. [ABSTRACT FROM AUTHOR]

This article aims to investigate the limitations on the amplitude of the conventional step recovery diode (SRD)-based Gaussian pulse transmitter and techniques to overcome the limits. The operation of the modified design is examined and compared with a conventional configuration. The results show a considerable increase in the pulse amplitude. The high pulse amplitude of the modified configuration represents an increase in the transmitter’s output power and its improved probing range. The Gaussian pulse is converted into the first derivative Gaussian pulse using a 90° broadband coupler as a differentiator and a semi-differentiator delay line circuit with balanced stubs. The output monopulse generated using the balanced stub delay line has more symmetric sidelobes with narrower pulsewidth than the 90° couplers. Experimental results have shown the high performance of the proposed transmitter over the conventional designs in terms of pulse amplitude and symmetry. [ABSTRACT FROM AUTHOR]

Long pulse gas lasers utilizing double-discharge circuits are different from the single-short pulse gas lasers in that they do not require all of the desired energy to be deposited into the peaking capacitors prior to ignition of the main gap. Instead, the majority of the energy is held in another capacitor that is then discharged in the form of a longer duration discharge pulse output compared with that of single-short pulse lasers. Extended stability of the discharge is typically achieved by igniting the main gap discharge at higher ignition voltages. Several double-discharge circuit topologies exist in the literature. However, each topology has its own disadvantages primarily centered around the components needed and the resulting complexity. In this article we introduce the application of the new hybrid circuit pulsed power topology as a double-discharge circuit with high ignition voltages. The hybrid circuit pulsed power topology was originally published by the authors of this article in their previous publication titled “A New Hybrid Pulsed Power Circuit Topology for Gas Laser Applications.” The advantage of the hybrid circuit as a double-discharge circuit is that it does not require any special device [e.g., semiconductor opening switch (SOS) diode] and can use commonly available components. [ABSTRACT FROM AUTHOR]

Nanoelectromechanical (NEM) switches offer the advantages of zero OFF-state leakage current, abrupt switching characteristics, nonvolatile (NV) operation, and relatively low ON-state resistance as compared with CMOS transistors predominantly used for digital computing today. NEM switches can be implemented using metallic interconnect layers formed in the back-end-of-line (BEOL) steps of a standard CMOS IC manufacturing process, in order to enable compact implementation of hybrid CMOS-NEM circuits. In this article, a release-etch method is developed for realizing BEOL NV-NEM switches with $\leq 100$ -nm contact gaps. A functional array of BEOL NV-NEM switches is used to implement a hybrid CMOS-NEM IC for data search applications. NV-NEM switch design optimization to minimize the programming voltage and accelerate switching speed is discussed. A scaled NV-NEM technology is projected to be advantageous for high-speed, low-power reconfigurable computing applications. This projection is validated with experimental data for a BEOL NV-NEM switch implemented with a conventional 16-nm CMOS IC manufacturing process. [ABSTRACT FROM AUTHOR]