Now showing items 1-20 of 303

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      Generation and design of sinusoidal oscillators using OTAS  [Presentation]

      Linares Barranco, Bernabé; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis; Sánchez Sinencio, Edgar; Hoyle, Javier J. (Institute of Electrical and Electronics Engineers, 1988)
      The design of voltage-controlled oscillators (VCOs) using operational transconductance amplifiers (OTAs) is discussed. Several oscillator structures are proposed. They use only OTAs and capacitors (OTA-C) and are very ...
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      Nonlinear time-domain macromodeling of OTA circuits  [Presentation]

      Pérez Verdú, Belén; Cruz Moreno, J.; Linares Barranco, Bernabé; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis; Sánchez Sinencio, Edgar (Institute of Electrical and Electronics Engineers, 1989)
      The authors present an accurate nonlinear macromodel of the operational transconductance amplifier (OTA) which is suitable for the transient simulation of OTA-based CMOS analog integrated circuits. As compared to device-level ...
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      A novel CMOS analog neural oscillator cell  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Newcomb, Robert W.; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1989)
      A very flexible programmable CMOS analog neural oscillator cell architecture is presented. The proposed neuron circuit architecture is a hysteretic neural-type pulse oscillator. Its implementation consists of a transconductance ...
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      Application of piecewise-linear switched-capacitor circuits for random number generation  [Presentation]

      Espejo Meana, Servando Carlos; Martín Gómez, José Domingo; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1989)
      An unconventional application of switched-capacitor (SC) circuits is discussed. A systematic method for the design of piecewise-linear (PL) parasitic-insensitive SC chaotic discrete maps is given. A simple circuit which ...
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      Analog integrated neural-like circuits for nonlinear programming  [Presentation]

      Rodríguez Vázquez, Ángel Benito; Domínguez Castro, Rafael; Huertas Díaz, José Luis; Sánchez Sinencio, Edgar (Institute of Electrical and Electronics Engineers, 1989)
      A systematic approach for the design of analog neural nonlinear programming solvers using switched-capacitor (SC) integrated circuit techniques is presented. The method is based on formulating a dynamic gradient system ...
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      OTA-based non-linear function approximations  [Presentation]

      Sánchez Sinencio, Edgar; Ramírez Angulo, Jaime; Linares Barranco, Bernabé; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1989)
      The suitability of operational transconductance amplifiers (OTAs) as the main active element to obtain basic building blocks for the design of programmable nonlinear continuous-time networks is examined. The main purpose ...
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      CMOS circuit implementations for neuron models  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1990)
      The mathematical neuron basic cells used as basic cells in popular neural network architectures and algorithms are discussed. The most popular neuron models (without training) used in neural network architectures and ...
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      Accurate design of analog CNN in CMOS digital technologies  [Presentation]

      Rodríguez Vázquez, Ángel Benito; Domínguez Castro, Rafael; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1990)
      Explores the design of cellular neural networks (CNN) by using sampled-data analog current-mode techniques which neither requires capacitors nor resistors but just MOS transistors. The feature makes the proposed technique ...
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      A CMOS Implementation of Fitzhugh-Nagumo Neuron Model  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1990)
      A CMOS circuit is proposed that emulates FitzHugh-Nagumo's differential equations using OTAs, diode connected MOSFETs and capacitors. These equations model the fundamental behavior of biological neuron cells. Fitz- ...
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      Very high frequency CMOS OTA-C quadrature oscillators  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1990)
      An approach to the design of high-frequency monolithic voltage-controlled oscillators using operational transconductance amplifiers and capacitors is given. Results from two 3 μm CMOS prototypes are presented. Both frequency ...
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      Design of an analog/digital truly random number generator  [Presentation]

      Espejo Meana, Servando Carlos; Martín, J. D.; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1990)
      An analog-digital system is presented for the generation of truly random (aperiodic) digital sequences. This model is based on a very simple piecewise-linear discrete map which is suitable for implementation using monolithic ...
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      Analog neural networks for real-time constrained optimization  [Presentation]

      Domínguez Castro, Rafael; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis; Sánchez Sinencio, Edgar; Linares Barranco, Bernabé (Institute of Electrical and Electronics Engineers, 1990)
      Architectures and circuit techniques for implementing general piecewise constrained optimization problems using VLSI techniques are explored. Discrete-time analog techniques are considered due to their inherent accuracy, ...
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      VLSI implementation of a transconductance mode continuous BAM with on chip learning and dynamic analog memory  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1991)
      In this paper we present a complete VLSI Continuous-Time Bidirectional Associative Memory (BAM). The short term memory (STM) section is implemented using small transconductance four quadrant multipliers, and capacitors for ...
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      An advanced symbolic analyzer for the automatic generation of analog circuit design equations  [Presentation]

      Fernández Fernández, Francisco Vidal; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1991)
      A tool for symbolic analysis of analog integrated circuits is presented featuring accurate simplification, pole/zero extraction, and tools for parametric AC circuit characterization. The program, called ASAP, uses signal ...
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      Hysteresis based neural oscillators for VLSI implementations  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1991)
      The actual tendency in most of the work that is being done in VLSI neural network research is to use the simplest possible models to perform the desired tasks. This yields to the use of sigmoidal type neurons that have ...
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      Frequency tuning loop for VCOs  [Presentation]

      Linares Barranco, Bernabé; Rodríguez Vázquez, Ángel Benito; Sánchez Sinencio, Edgar; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1991)
      A frequency tuning circuit is introduced for VCOs (voltage-controlled oscillators) so that the final relationship between oscillating frequency and input control voltage is fixed and independent of nonidealities. This ...
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      Design of RC-active oscillators using composite amplifiers  [Presentation]

      Pérez Verdú, Belén; Huertas Díaz, José Luis; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1991)
      The design of composite opamp Wien-Bridge oscillators is systematically approached by using a general model including amplitude control issues. Two different design criteria are presented and their main features summarized. ...
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      A piecewise-linear function approximation using current mode circuits  [Presentation]

      Ramírez Angulo, Jaime; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1992)
      A methodology to design currentmode circuits for piecewise-linear function approximation is presented. The technique is based on the utilization of current mirrors as basic building blocks. The resulting circuits are very ...
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      A prototype tool for optimum analog sizing using simulated annealing  [Presentation]

      Medeiro Hidalgo, Fernando; Domínguez Castro, Rafael; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1992)
      It is shown that using simulated annealing in combination with electrical simulation provides a powerful tool allowing unexperienced designer to size complex analogue building blocks starting from scratch. A cost function ...
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      Modular analog continuous-time VLSI neural networks with on chip hebbian learning and analog storage  [Presentation]

      Linares Barranco, Bernabé; Sánchez Sinencio, Edgar; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institute of Electrical and Electronics Engineers, 1992)
      A modular analog circuit design approach for hardware implementations of neural networks is presented. This approach is based on the use of small transconductance multipliers as the main component, and is therefore called ...