113 lines
4.0 KiB
TeX
113 lines
4.0 KiB
TeX
\documentclass{beamer}
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%\usepackage{auto-pst-pdf}
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\usepackage{graphicx}
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\begin{document}
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\begin{frame}
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\frametitle{Kelvin Ly}
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Hi Neocis!
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\end{frame}
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\begin{frame}
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\frametitle{Introduction}
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\begin{itemize}
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\item BSEE and MsEE at University of Central Florida
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\begin{itemize}
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\item Research work in hardware security
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\item PCB design, FPGA work
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\end{itemize}
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\item Electrical engineer at STERIS IMS
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\begin{itemize}
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\item Reverse engineering medical devices
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\item Design, layout, testing of replacement PCBAs
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\item High speed, some high density, FPGA
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\item Tons of protocols (SPI, I2C, UART, SWI, SWD, SBW, USB 2.0, JTAG, MIPI CSI-2, HyperRAM, NFC Type V)
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\item FPGA stuff, image processing
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\end{itemize}
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\item Side jobs/projects
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\begin{itemize}
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\item A little bit of everything
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\item Two side jobs
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\begin{itemize}
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\item Fluorometric Instruments, industrial chemical sensors
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\item Cassina Technologies, company one of my coworkers runs on the side
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\end{itemize}
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\item Mixed signal design, FPGA, some RF design
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\item Working on the mechanical design for a CNC right now
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\end{itemize}
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\end{itemize}
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\end{frame}
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\begin{frame}
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\frametitle{Optical communications project}
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\begin{itemize}
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\item I designed this years ago, hindsight is 20-20
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\item Design parameters
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\begin{itemize}
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\item Low bitrate unidirectional communication
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\item Moderate range
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\item White LED for transmitter, photodiode as receiver
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\item USB interface
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\end{itemize}
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\item Objectives
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\begin{itemize}
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\item High dynamic range (want to be very tolerant of beam angle)
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\item Huge emphasis on noise analysis
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\item Highly flexible (I have no idea what I'm doing and I don't want to pay for a second board spin)
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\item Let's do a lot of signal processing because I don't know a lot of that
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\end{itemize}
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\end{itemize}
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\end{frame}
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\begin{frame}
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\frametitle{Front end}
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\begin{columns}
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\begin{column}{0.4\textwidth}
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\begin{figure}
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\includegraphics[angle=270, bb=0.5in 1.8in 5in 5.4in, scale=0.5, clip]{receiver-Photodiode.eps}
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\end{figure}
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\end{column}
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\begin{column}{0.6\textwidth}
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\begin{itemize}
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\item Largely based on Chapter 18 of Building Electro-optical Systems by Philips C. D. Hobbs
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\item Also Analog Devices Design Note 399
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\item TIA with some extra bells and whistles
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\item Lots of noise analysis, some stability analysis
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\item BJTs act to remove voltage offset
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\item JFET acts as a low noise bootstrap to reduce effect of photodiode capacitance
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\end{itemize}
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\end{column}
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\end{columns}
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\end{frame}
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\begin{frame}
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\frametitle{Way too many amplifier stages}
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\begin{figure}
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\centerline{
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\includegraphics[angle=270, bb=0.5in 4.9in 5in 11.3in, scale=0.5, clip]{receiver-Photodiode.eps}
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}
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\end{figure}
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\end{frame}
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\begin{frame}
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\frametitle{Way too many amplifier stages}
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\begin{itemize}
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\item Lots of gain on the front so that the added noise is minimized
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\item Lots of adjustable gain and rudimentary bandpass filtering
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\item ATtiny412 setting gain on the JFET stage
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\end{itemize}
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\end{frame}
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\begin{frame}
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\frametitle{Digital side}
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\includegraphics[angle=270, scale=0.3, bb=0.5in 0.5in 7.3in 11.2in, clip]{receiver-Digital.eps}
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\begin{itemize}
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\item 12-bit discrete ADC into STM32 micro
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\item USB interface directly from STM32 micro, useful for high bitrate of ADC channel
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\end{itemize}
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\end{frame}
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\begin{frame}
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\frametitle{Lessons learned}
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\begin{itemize}
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\item Debuggability is an important design factor
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\item Less is more
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\item Break projects into smaller steps
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\item Questions?
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\end{itemize}
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\end{frame}
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\end{document}
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