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Micromachined technology makes it possible to integrate the ultrasonic sensor with the front-end processing circuit together, and make an ultrasonic system smart, compact and low cost. An ultrasonic sensor array with resonant frequency of about 60 kHz is fabricated for airborne applications, using sol-gel derived Pb(Zr, Ti)O[sub 3] thin film and Si-based micromachining technique. The distributed delay-sum architecture based on bucket brigade device is employed for the beam-forming of the sensor array in order to reduce chip area, simplify system design, improve power efficient and achieve monolithic integration. A charge attenuator is proposed to increase the dynamic range of the input signal and overcome the charge overflowing in bucket capacitors. A charge amplifier based preamplifier is used to interface the sensor array and beamformer. A prototype front-end processor shows good SNR with the dynamic range larger than 50 dB, and a beamforming performance consistent to the theoretical calculation very well. [ABSTRACT FROM AUTHOR]

The superconductor single-flux-quantum (SFQ) logic family has been recognized as a promising solution for the post-Moore era, thanks to the ultrafast and low-power switching characteristics of superconductor devices. Researchers have made tremendous efforts in various aspects, especially in device and circuit design. However, there has been little progress in designing a convincing SFQ-based architectural unit due to a lack of understanding about its potentials and limitations at the architectural level. This article provides the design principles for SFQ-based architectural units with an extremely high-performance neural processing unit (NPU). To achieve our goal, we developed and validated a simulation framework to identify critical architectural bottlenecks in designing a performance-effective SFQ-based NPU. We propose SuperNPU, which outperforms a conventional state-of-the-art NPU by 23 times in terms of computing performance and 1.23 times in power efficiency even with the cooling cost of the 4K environment. [ABSTRACT FROM AUTHOR]

Hybrid electric vehicles (HEVs) that emit less carbon dioxide have attracted much attention and rapidly become widespread, but further popularization of HEVs requires further technical advancement of mounted traction motors. Accordingly, our research group focuses on axial gap motors that can realize high torque density. In this paper, an axial gap motor with a novel interior permanent magnet (IPM) rotor structure is proposed and an examination of the proposed motor at the actual motor size of an HEV is presented. For comparison, we selected the newest radial gap-type 60 kW IPM synchronous motor equipped in the third-generation Toyota Prius. Under the condition that the size of the proposed motor be the same as the comparison motor, we confirmed through three-dimensional finite-element analysis that the proposed motor could output twice the maximum torque of the comparison motor. In addition, a comparison was made with a previously reported conventional IPM-type axial gap motor, and the proposed motor was found to be more effective in generating reluctance torque. Moreover, the proposed motor exhibited sufficient durability to irreversible demagnetization of the permanent magnets, to stress caused by rotating the rotor, and to unbalanced electromagnetic forces caused by axial rotor eccentricity. [ABSTRACT FROM AUTHOR]

We report the progress in the development of an Operand Routing Network (ORN) for an SFQ Reconfigurable Data-Paths processor (SFQ-RDP). The SFQ-RDP is implemented as a two-dimensional array of Floating-Point Units (FPU), outputs of which can be connected to the inputs of one or more FPUs in the next row via ORN. We have considered two architectures of the ORN: one is based on NDRO switches and the other — on crossbar switches. The comparison shows that the crossbar-based ORN has better performance due to the regular pipelined structure. We have designed a crossbar switch with a multicasting function and a 1-to-2 ORN prototype for 2.5 kA/cm2 process. The circuits have been experimentally tested at the frequencies up to 36 GHz. [ABSTRACT FROM AUTHOR]