IFAE People

José Gabriel Macías

José Gabriel Macías

José Gabriel Macías

Microelectronics Design Engineer

  • About Me

    I am a senior research engineer working in the field of microelectronics design and ultra-low noise electronics for many and diverse applications since 1999. My background in physics and electrical engineering allows me to investigate the basics of noise and how to overcome the physical limitations in readout systems.

    From 1999 until 2010 I worked in several European research institutions such as the University of Barcelona in Spain, the Institute of Microelectronics of Frankfurt (Oder) in Germany, and the Delft University of Technology in the Netherlands. In these years, my research was focused to circuits working at radiofrequencies and microwaves for ultra-low-power communications and radio devices. During the periods at the University of Barcelona, I was appointed as well as assistant professor and taught electronic and microelectronic design subjects.

    In November 2010 I joined the Institute of high energy physics (IFAE) of Barcelona in the frame of an ERC project. Since then we developed several readout ASICs for high energy particle and photons detection for medical imaging and non-intrusive inspection applications. Since 2014, I re-joined the University of Barcelona as a part-time assistant professor.

    I am co-inventor of two patents, one in the field of communications devices and another with pixelated cameras for high energy particle detection. Additionally, I am the only inventor of my last patent, which breaks with the rational thinking used in actual communications systems enabling to double the actual data rate.

    For me, the biggest challenge in electronics and microelectronics is the development of graphene and 2D materials technologies and designs to overcome actual limits in terms of power consumption, speed, and of course, noise.

  • Research

    For an electrical engineer, there are few lines to do research: ultra-low power, ultra-low noise, very high speed, high power, and digital algorithms and architectures among few more. I chose ultra-low noise and ultra-low power electronics because it is always more efficient to obtain 3 dB improvement in noise rejection than increasing 3 dB the output power of a communications antenna.

    More than half of my career I worked as Radiofrequency and microwave designer. I implemented all kind of circuits of a communications link such as low-noise amplifiers, voltage-controlled oscillators, frequency mixers and synthesizers, and phase-lock loops for different projects, European and national ones.

    Most of the research in that period was related to a new type of oscillator and its applications: the second-harmonic injection-locked oscillator (2nd Harmonic ILO). Two of my patents are based on the performance and working principle of these kind of oscillators. The basics are that a voltage-controlled oscillator working at a frequency fVCO can be synchronized to a frequency fSYNC by injecting in a common-mode signal node of the circuit an AC signal at a frequency twice fSYNC. Originally, there was a very common application for this oscillator which comes naturally: a frequency and phase divider. Nevertheless, during our research at the University of Barcelona we developed new analytical models with more accurate phase description of the 2nd Harmonic ILOs. Finally, up to five novel circuits based on 2nd Harmonic ILOs have been invented and two of them were patented.

    In November 2010 I joint IFAE to develop a readout ASIC for a novel Positron Emission Tomography scanner based on pixelated solid state detectors made of Cadmium Telluride. The chip was developed with a minimum team of 1 full time designer (Jose Gabriel Macias), one consultor and a layout editor located at the USA, and a part time (10%) digital algorithm designer from the “Institut de Microelectrònica de Barcelona - Centre Nacional de Microelectrònica IMB-CNM”. The results of the ASICs have been published and presented at international conferences and symposiums. The novel positron emission tomography scanner is under evaluation from mid 2017 when all detection modules have been completed.

    We developed a second ASIC for Cadmium Telluride detectors but in this case for X-Ray detection and imaging using the photon-counting technique. ERICA is the name of the project involved and so the name of the ASIC. It composes of 160 readout pixels with six energy bins resolving photon-counting electronics. Note that one object scanned one time with a continuous spectrum X-ray tube will provide 6 different images, one for every energy range of the incoming X-Ray photons. With this technique, different density tissues can be easily differentiated in a X-Ray image. The results of the ASIC have been presented at the 2016 IWORiD conference in Barcelona with a poster – mini oral presentation.

    In the present, I am involved in two different projects: an ultra-low noise discrete electronics for the characterization of novel gamma-ray detectors based on Perovskites (BIST-ZPRO), and complete stimulation system for retinal ganglion cells stimulation and imaging (BIST-THEIA).

  • Publications

    Selected publications:

    • ERICA: an energy resolving photon counting readout ASIC for X-ray in-line cameras, Macías-Montero J.G., et al. Journal of Instrumentation, Volume 11, December 2016, page(s): 20 – 27

    • A 2D 4x4 channel readout ASIC for pixelated CdTe detectors for medical imaging applications,Macias-Montero J.G., et al. IEEE Transaction of Nuclear Science, Volume 62, Issue 5, Oct. 2015, Page(s): 2327 – 2333

    • Toward VIP-PIX: A Low Noise Readout ASIC for Pixelated CdTe Gamma-Ray Detectors for Use in the Next Generation of PET Scanners, Macias-Montero, J.G., et al. IEEE Transactions on Nuclear Science, 60-4/Part 2, pp. 2898-2904. IEEE, 2013

    • IQ signal generator using 2nd-harmonic injection locked oscillator, Lopez-Villegas, Jose M.; Vidal, Neus; Sieiro, Javier; Macias-Montero, J.G. Microwave Symposium Digest (MTT), 2012 IEEE MTT-S International, 2012, Page(s): 1 – 3

    • An Ultra-Low_Power BPSK Receiver and Demodulator Based on Injection-Locked Oscillators, Han Yan; Macias-Montero, J.G.; Akhouukh, A.; de Vreede, L.C.N.; Long, J.R.; Burghartz, J.N. IEEE Transactions on Microwave Theory and Techniques, Vol. 59- 5, 2011 pp: 1339 – 1349

  • Projects

    Selected projects:

    • BIST – ZPRO
      Programme: Barcelona Institute of Science and Technology (BIST) 2016 IGNITE call
      Members: Institute of chemical research of Catalonia (ICIQ), IFAE

    • BIST – THEIA
      Programme: Barcelona Institute of Science and Technology (BIST) 2016 IGNITE call
      Members: ICFO, ICN2, IFAE

    • ERICA: Energy Resolving In-Line Camera
      Programme: RETOS-COLABORACIÓN 2014
      Members: X-Ray Imatek S.L., Multiscan Technologies S.L., IFAE

    • CTA – Trigger Level 0 – Fanout
      Programme: Cherenkov Telescope Array Collaboration
      Members: CIEMAT, UB, Universidad de Jaén, UCM, CSIC, IFAE, PIC, UAB, ICREA, IEEC

    • VIP Voxel Imaging PET Pathfinder
      Programme: European Research Council Advanced grant 2010
      Members: IFAE

  • Talks

    Selected scientific talks:

    • A 2D 4x4 Channel Readout ASIC for Pixelated CdTe Detectors for Medical Imaging Applications
      IEEE Nuclear Science Symposium, Oct-27 – Nov-2 2013, Seoul, Korea
      NSS-MIC-RTSD Joint Session J3-7

    • VIP-PIX: a Low Noise Readout ASIC for Pixelated CdTe Gamma-Ray Detectors for Use in the Next Generation of PET Scanners
      IEEE Nuclear Science Symposium, Oct-29 – Nov-3, 2012, Anaheim, California, USA
      NSS Session N16-3 Analog and Digital Circuits IV

  • Outreach

    Selected outreach activities:

    • Medical Imaging IFAE’s activities talk for BIST Ph.D. students and Post-Doc researchers.
      IFAE – Spring 2017

    • Assistant Professor at the University of Barcelona since 2015 Microelectronics Design – Laboratory and Problems Laboratory of Electronic Systems I – Design and Implementation of a Drone.

  • Patents

    Selected patents

    • Method for modulating and demodulating PSK signals and demodulator thereof
      Inventor: José Gabriel Macías Montero
      PCT/EP2016/064258 from 21.06.16

    • Energy sum with photon counting
      Inventors: M. Chmeissani, J.G. Macias Montero, M. Kolstein
      EP15382072.5 from 23.02.15

    • A system for demodulation of phase shift keying signals
      Inventors: J. López-Villegas, J. Osorio Marti, J.G. Macias Montero, J. Cairo Molins
      EP20070380075 from 19.03.07