Now showing items 1-20 of 520

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      Novel active-compensated weighted summer  [Article]

      Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis (Institution of Engineering and Technology, 1980)
      A summer amplifier with extended bandwidth is proposed. Compensation of the frequency characteristics is achieved by employing two operational amplifiers instead of external reactive components.
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      Nonlinear switched-current CMOS IC for random signal generation  [Article]

      Delgado Restituto, Manuel; Medeiro Hidalgo, Fernando; Rodríguez Vázquez, Ángel Benito (Institution of Engineering and Technology, 1993)
      A nonlinear switched-current circuit is presented that implements a chaotic algorithm for the generation of broadband, white analogue noise. The circuit has been fabricated in a double-metal, single-poly 1.6µm CMOS technology ...
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      New analogue switch circuit having very low forward resistance  [Article]

      Huertas Díaz, José Luis; Rodríguez Vázquez, Ángel Benito; Rueda Rueda, Adoración (Institution of Engineering and Technology, 1984)
      A new circuit realisation for an analogue switch is reported. The main feature of the proposed design is the low value of the forward resistance as compared with commercial switches. Experimental data confirming the ...
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      Error control in simplification before generation algorithms for symbolic analysis of large analogue circuits  [Article]

      Rodríguez García, Juan D.; Guerra Vinuesa, Oscar; Roca Moreno, Elisenda; Fernández Fernández, Francisco Vidal; Rodríguez Vázquez, Ángel Benito (Institution of Engineering and Technology, 1999)
      Circuit reduction is a fundamental first step in addressing the symbolic analysis of large analogue circuits. A new algorithm for simplification before generation is presented which is very efficient in terms of speed and ...
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      CMOS optical-sensor array with high output current levels and automatic signal-range centring  [Article]

      Espejo Meana, Servando Carlos; Domínguez Castro, Rafael; Carmona Galán, Ricardo; Rodríguez Vázquez, Ángel Benito (Institution of Engineering and Technology, 1994)
      A CMOS compatible photosensor with high output current levels, and an area-efficient scheme for automatic signal-range centring according to illumination conditions are presented. The high output current levels allow the ...
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      CMOS 2.4μm chaotic oscillator: Experimental verification of chaotic encryption of audio  [Article]

      Delgado Restituto, Manuel; Liñán Cembrano, Gustavo; Rodríguez Vázquez, Ángel Benito (Institution of Engineering and Technology, 1996)
      The Letter reports the first experimental verification of chaotic encryption of audio using custom monolithic chaotic oscillators. We use Gm-C techniques to realise a chaotic modulator/ demodulator IC that implements a ...
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      Algorithm for efficient symbolic analysis of large analogue circuits  [Article]

      Wambacq, Piet; Gièlen, Georges G.E.; Sansen, Willy M.C.; Rodríguez Vázquez, Ángel Benito; Fernández Fernández, Francisco Vidal (Institution of Engineering and Technology, 1994)
      An algorithm is presented that generates simplified symbolic expressions for the small-signal characteristics of large analogue circuits. The expressions are approximated while they are computed, so that only the most ...
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      A switched-capacitor broadband noise generator for CMOS VLSI  [Article]

      Rodríguez Vázquez, Ángel Benito; Delgado Restituto, Manuel; Espejo Meana, Servando Carlos; Huertas Díaz, José Luis (Institution of Engineering and Technology, 1991)
      A switched-capacitor circuit is reported for the generation of broadband white noise in MOS VLSI. It is based on the implementation of a very simple chaotic discrete-time system. The concept is demonstrated via a 3ftm CMOS ...
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      Does the use of nest materials in a ground-nesting bird result from a compromise between the risk of egg overheating and camouflage?  [Article]

      Gómez, Jesús; Liñán Cembrano, Gustavo; Ramo, Cristina; Castro, Macarena; Pérez Hurtado, Alejandro; Amat, Juan A. (Company of Biologists, 2019)
      Many studies addressing the use of nest materials by animals have focused on only one factor to explain its function. However, the consideration of more than one factor could explain the apparently maladaptive choice of ...
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      10mhz cmos ota-c voltage-controlled quadrature oscillator  [Article]

      Linares Barranco, Bernabé; Rodríguez Vázquez, Ángel Benito; Sánchez Sinencio, Edgar; Huertas Díaz, José Luis (Institution of Engineering and Technology, 1989)
      A quadrature-type voltage-controlled oscillator with operational transconductance amplifiers and capacitors (OTA-C) is presented. A monolithic integrated CMOS test circuit is introduced to verify theoretical results. The ...
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      Smart-Pixel Cellular Neural Networks in Analog Current-Mode CMOS Technology  [Article]

      Espejo Meana, Servando Carlos; Rodríguez Vázquez, Ángel Benito; Domínguez Castro, Rafael; Huertas Díaz, José Luis; Sánchez Sinencio, Edgar (Institute of Electrical and Electronics Engineers, 1994)
      This paper presents a systematic approach to design CMOS chips with concurrent picture acquisition and processing capabilities. These chips consist of regular arrangements of elementary units, called smart pixels. Light ...
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      Efficient symbolic computation of approximated small-signal characteristics of analog integrated circuits  [Article]

      Wambacq, Piet; Fernández Fernández, Francisco Vidal; Gielen, Georges; Sansen, Willy M.C.; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1995)
      A symbolic analysis tool is presented that generates simplified symbolic expressions for the small-signal characteristics of large analog integrated circuits. The expressions are approximated while they are computed, so ...
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      Analog Neural Programmable Optimizers in CMOS VLSI Technologies  [Article]

      Domínguez Castro, Rafael; Rodríguez Vázquez, Ángel Benito; Huertas Díaz, José Luis; Sánchez Sinencio, Edgar (Institute of Electrical and Electronics Engineers, 1992)
      A 3-μm CMOS IC is presented demonstrating the concept of an analog neural system for constrained optimization. A serial time-multiplexed general-purpose architecture is introduced for the real-time solution of this kind ...
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      A mixed-signal integrated circuit for FM-DCSK modulation  [Article]

      Delgado Restituto, Manuel; Acosta Jiménez, Antonio José; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 2005)
      This paper presents a mixed-signal application-specific integrated circuit (ASIC) for a frequency-modulated differential chaos shift keying (FM-DCSK) communication system. The chip is conceived to serve as an experimental ...
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      A 0.8-μm CMOS two-dimensional programmable mixed-signal focal-plane array processor with on-chip binary imaging and instructions storage  [Article]

      Domínguez Castro, Rafael; Espejo Meana, Servando Carlos; Rodríguez Vázquez, Ángel Benito; Carmona Galán, Ricardo; Földesy, Péter; Zarándy, Ákos; Szolgay, Péter; Szirányi, Tamás; Roska, Tamás (Institute of Electrical and Electronics Engineers, 1997)
      This paper presents a CMOS chip for the parallel acquisition and concurrent analog processing of two-dimensional (2-D) binary images. Its processing function is determined by a reduced set of 19 analog coefficients whose ...
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      A 13-bit, 2.2-MS/s, 55-mW multibit cascade ΣΔ modulator in CMOS 0.7-μm single-poly technology  [Article]

      Medeiro Hidalgo, Fernando; Pérez Verdú, Belén; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1999)
      This paper presents a CMOS 0.7-μm ΣΔ modulator IC that achieves 13-bit dynamic range at 2.2 MS/s with an oversampling ratio of 16. It uses fully differential switched-capacitor circuits with a clock frequency of 35.2 MHz, ...
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      A new nonlinear time-domain op-amp macromodel using threshold functions and digitally controlled network elements  [Article]

      Pérez Verdú, Belén; Huertas Díaz, José Luis; Rodríguez Vázquez, Ángel Benito (Institute of Electrical and Electronics Engineers, 1988)
      A general-purpose nonlinear macromodel for the time-domain simulation of integrated circuit operational amplifiers (op amps), either bipolar or MOS, is presented. Three main differences exist between the macromodel and ...
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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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      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 ...