High-frequency two-input CMOS OTA for continuous-time filter applications

“This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.”A high-frequency fully differential CMOS operational transconductance amplifier (OTA) is presented for continuous-time filter applications in the megahertz range. The proposed design technique combines a linear cross-coupled quad input stage with an enhanced folded-cascode circuit to increase the output resistance of the amplifier. SPICE simulations show that DC-gain enhancement can be obtained without significant bandwidth limitation. The two-input OTA developed is used in high-frequency tuneable filter design based on IFLF and LC ladder simulation structures. Simulated results of parameters and characteristics of the OTA and filters in a standard 1.2 μm CMOS process (MOSIS) are presented. A tuning circuit is also discussed.Peer reviewe

Finite-element analyses of blade and slot coating flows using an implicit pseudo-solid domain mapping technique coupled with unstructured grids

In coating processes (e.g. in blade coating) the flow domain inherently contains free surfaces and three-phase contact lines, and characteristic length scales of flow features in the dimension transverse to the web-movement vary by an order of magnitude or more from a fraction of a millimeter or more to tens of microns or less). The presence of free surfaces and three-phase contact lines, and the sudden changes of flow geometry and directions create difficulties in theoretical analyses of such flows. Though simulations of coating flows via finite-element methods using structured grids have been reportedly demonstrated in the literature, achieving high efficiency of such numerical experiments remains a grand challenge -- mainly due to difficulties in local mesh-refinement and in avoiding unacceptably distorted grids. High efficiency of computing steady flow fields under various process conditions is crucial in shortening turn-around time in design and optimization of coating-flow processes. In this paper we employ a fully-implicit, pseudo-solid, domain mapping technique coupled with unstructured meshes to analyze blade and slot coating flows using Galerkin`s method with finite element basis functions. We demonstrate the robustness and efficiency of our unique technique in circumventing shortcomings of mesh-motion schemes currently being used in the coating-flow research community. Our goal is to develop an efficient numerical tool, together with a suitable optimization toolkit, that can be used routinely in design and optimization of coating-flow processes

High temperature solder alloys for underhood applications: Final report

In this continued study, the microstructural evolution and peel strength as a function of thermal aging were evaluated for four Sn-Ag solders deposited on double layered Ag-Pt metallization. Additionally, activation energies for intermetallic growth over the temperature range of 134 to 190{degrees}C were obtained through thickness measurements of the Ag-Sn intermetallic that formed at the solder-metallization interface. It was found that Bi-containing solders yielded higher activation energies for the intermetallic growth, leading to thicker intermetallic layers at 175 and 190{degrees}C for times of 542 and 20.5 hrs, respectively, than the solders free of Bi. Complete reaction of the solder with the metallization occurred and lower peel strengths were measured on the Bi-containing solders. In all solder systems, a Ag-Sn intermetallic thickness of greater than {approximately}7 {mu}m contributed to lower peel strength values. The Ag-Sn binary eutectic composition and the Ag-Sn-Cu ternary eutectic composition solders yielded lower activation energies for intermetallic formation, less microstructural change with time, and higher peel strengths; these solder systems were resilient to the effects of temperatures up to 175{degrees}C. Accelerated isothermal aging studies provide useful criteria for recommendation of materials systems. The Sn-Ag and Sn-Ag-Cu eutectic compositions should be considered for future service life and reliability studies based upon their performance in this study

High temperature solder alloys for underhood applications. Progress report

Under a cooperative research and development agreement with General Motors Corporation, lead-free solder systems including the flux, metallization, and solder are being developed for high temperature, underhood applications. Six tin-rich solders, five silver-rich metallizations, and four fluxes were screened using an experimental matrix whereby every combination was used to make sessile drops via hot plate or Heller oven processing. The contact angle, sessile drop appearance, and in some instances the microstructure was evaluated to determine combinations that would yield contact angles of less than 30{degrees}, well-formed sessile drops, and fine, uniform microstructures. Four solders, one metallization, and one flux were selected and will be used for further aging and mechanical property studies

Convolutional neural networks for image processing: an application in robot vision

adaptive image processing, and form a link between general feedforward neural networks and adaptive filters. Two dimensional CNNs are formed by one or more layers of two dimensional filters, with possible non-linear activation functions and/or down-sampling. Conventional neural network error minimization methods may be used to optimize convolutional networks in order to implement quite powerful image transformations. CNNs possess key properties of translation invariance and spatially local connections (receptive fields). CNNs are an interesting alternative when the the input is spatially or temporally distributed, and the desired output of a system may be specified. The present paper presents a description of the convolutional network architecture, and an application to a practical image processing application on a mobile robot. As a formal CNN framework has not yet been specified in the literature, we describe CNNs in some detail, conceptually and formally. A CNN is used to detect and characterize cracks on an autonomous sewer inspection robot. Although cracks are relatively easy to detect by a human operator, autonomous sewer inspection necessitate

Neural network applications in character recognition and document analysis

A proven strength of neural-network methods is their application to character recognition and document analysis. In this paper we describe a neural-net Optical Character Recognizer (OCR), neural-net preprocessing, and neuralnet hardware accelerators that together comprise a high-performance character recognition system. We also describe applications in networkbased fax and bit-mapped text processing