Low Power Multi-Channel Interface for Charge Based Tactile Sensors

Analog front end electronics are designed in 65 nm CMOS technology to process charge pulses arriving from a tactile sensor array. This is accomplished through the use of charge sensitive amplifiers and discrete time filters with tunable clock signals located in each of the analog front ends. Sensors were emulated using Gaussian pulses during simulation. The digital side of the system uses SAR (successive approximation register) ADCs for sampling of the processed sensor signals. Adviser: Sina Balkı

A full-custom digital-signal-processing unit for real-time cortical blood flow monitoring

Master'sMASTER OF ENGINEERIN

Architectural Exploration of KeyRing Self-Timed Processors

RÉSUMÉ Les dernières décennies ont vu l’augmentation des performances des processeurs contraintes par les limites imposées par la consommation d’énergie des systèmes électroniques : des très basses consommations requises pour les objets connectés, aux budgets de dépenses électriques des serveurs, en passant par les limitations thermiques et la durée de vie des batteries des appareils mobiles. Cette forte demande en processeurs efficients en énergie, couplée avec les limitations de la réduction d’échelle des transistors—qui ne permet plus d’améliorer les performances à densité de puissance constante—, conduit les concepteurs de circuits intégrés à explorer de nouvelles microarchitectures permettant d’obtenir de meilleures performances pour un budget énergétique donné. Cette thèse s’inscrit dans cette tendance en proposant une nouvelle microarchitecture de processeur, appelée KeyRing, conçue avec l’intention de réduire la consommation d’énergie des processeurs. La fréquence d’opération des transistors dans les circuits intégrés est proportionnelle à leur consommation dynamique d’énergie. Par conséquent, les techniques de conception permettant de réduire dynamiquement le nombre de transistors en opération sont très largement adoptées pour améliorer l’efficience énergétique des processeurs. La technique de clock-gating est particulièrement usitée dans les circuits synchrones, car elle réduit l’impact de l’horloge globale, qui est la principale source d’activité. La microarchitecture KeyRing présentée dans cette thèse utilise une méthode de synchronisation décentralisée et asynchrone pour réduire l’activité des circuits. Elle est dérivée du processeur AnARM, un processeur développé par Octasic sur la base d’une microarchitecture asynchrone ad hoc. Bien qu’il soit plus efficient en énergie que des alternatives synchrones, le AnARM est essentiellement incompatible avec les méthodes de synthèse et d’analyse temporelle statique standards. De plus, sa technique de conception ad hoc ne s’inscrit que partiellement dans les paradigmes de conceptions asynchrones. Cette thèse propose une approche rigoureuse pour définir les principes généraux de cette technique de conception ad hoc, en faisant levier sur la littérature asynchrone. La microarchitecture KeyRing qui en résulte est développée en association avec une méthode de conception automatisée, qui permet de s’affranchir des incompatibilités natives existant entre les outils de conception et les systèmes asynchrones. La méthode proposée permet de pleinement mettre à profit les flots de conception standards de l’industrie microélectronique pour réaliser la synthèse et la vérification des circuits KeyRing. Cette thèse propose également des protocoles expérimentaux, dont le but est de renforcer la relation de causalité entre la microarchitecture KeyRing et une réduction de la consommation énergétique des processeurs, comparativement à des alternatives synchrones équivalentes.----------ABSTRACT Over the last years, microprocessors have had to increase their performances while keeping their power envelope within tight bounds, as dictated by the needs of various markets: from the ultra-low power requirements of the IoT, to the electrical power consumption budget in enterprise servers, by way of passive cooling and day-long battery life in mobile devices. This high demand for power-efficient processors, coupled with the limitations of technology scaling—which no longer provides improved performances at constant power densities—, is leading designers to explore new microarchitectures with the goal of pulling more performances out of a fixed power budget. This work enters into this trend by proposing a new processor microarchitecture, called KeyRing, having a low-power design intent. The switching activity of integrated circuits—i.e. transistors switching on and off—directly affects their dynamic power consumption. Circuit-level design techniques such as clock-gating are widely adopted as they dramatically reduce the impact of the global clock in synchronous circuits, which constitutes the main source of switching activity. The KeyRing microarchitecture presented in this work uses an asynchronous clocking scheme that relies on decentralized synchronization mechanisms to reduce the switching activity of circuits. It is derived from the AnARM, a power-efficient ARM processor developed by Octasic using an ad hoc asynchronous microarchitecture. Although it delivers better power-efficiency than synchronous alternatives, it is for the most part incompatible with standard timing-driven synthesis and Static Timing Analysis (STA). In addition, its design style does not fit well within the existing asynchronous design paradigms. This work lays the foundations for a more rigorous definition of this rather unorthodox design style, using circuits and methods coming from the asynchronous literature. The resulting KeyRing microarchitecture is developed in combination with Electronic Design Automation (EDA) methods that alleviate incompatibility issues related to ad hoc clocking, enabling timing-driven optimizations and verifications of KeyRing circuits using industry-standard design flows. In addition to bridging the gap with standard design practices, this work also proposes comprehensive experimental protocols that aims to strengthen the causal relation between the reported asynchronous microarchitecture and a reduced power consumption compared with synchronous alternatives. The main achievement of this work is a framework that enables the architectural exploration of circuits using the KeyRing microarchitecture

Circuit-Variant Moving Target Defense for Side-Channel Attacks on Reconfigurable Hardware

With the emergence of side-channel analysis (SCA) attacks, bits of a secret key may be derived by correlating key values with physical properties of cryptographic process execution. Power and Electromagnetic (EM) analysis attacks are based on the principle that current flow within a cryptographic device is key-dependent and therefore, the resulting power consumption and EM emanations during encryption and/or decryption can be correlated to secret key values. These side-channel attacks require several measurements of the target process in order to amplify the signal of interest, filter out noise, and derive the secret key through statistical analysis methods. Differential power and EM analysis attacks rely on correlating actual side-channel measurements to hypothetical models. This research proposes increasing resistance to differential power and EM analysis attacks through structural and spatial randomization of an implementation. By introducing randomly located circuit variants of encryption components, the proposed moving target defense aims to disrupt side-channel collection and correlation needed to successfully implement an attac

Analysis and Optimization for Pipelined Asynchronous Systems

Most microelectronic chips used today--in systems ranging from cell phones to desktop computers to supercomputers--operate in basically the same way: they synchronize the operation of their millions of internal components using a clock that is distributed globally. This global clocking is becoming a critical design challenge in the quest for building chips that offer increasingly greater functionality, higher speed, and better energy efficiency. As an alternative, asynchronous or clockless design obviates the need for global synchronization; instead, components operate concurrently and synchronize locally only when necessary. This dissertation focuses on one class of asynchronous circuits: application specific stream processing systems (i.e. those that take in a stream of data items and produce a stream of processed results.) High-speed stream processors are a natural match for many high-end applications, including 3D graphics rendering, image and video processing, digital filters and DSPs, cryptography, and networking processors. This dissertation aims to make the design, analysis, optimization, and testing of circuits in the chosen domain both fast and efficient. Although much of the groundwork has already been laid by years of past work, my work identifies and addresses four critical missing pieces: i) fast performance analysis for estimating the throughput of a fine-grained pipelined system; ii) automated and versatile design space exploration; iii) a full suite of circuit level modules that connect together to implement a wide variety of system behaviors; and iv) testing and design for testability techniques that identify and target the types of errors found only in high-speed pipelined asynchronous systems. I demonstrate these techniques on a number of examples, ranging from simple applications that allow for easy comparison to hand-designed alternatives to more complex systems, such as a JPEG encoder. I also demonstrate these techniques through the design and test of a fully asynchronous GCD demonstration chip

A 128K-bit CCD buffer memory system

A prototype system was implemented to demonstrate that CCD's can be applied advantageously to the problem of low power digital storage and particularly to the problem of interfacing widely varying data rates. 8K-bit CCD shift register memories were used to construct a feasibility model 128K-bit buffer memory system. Peak power dissipation during a data transfer is less than 7 W., while idle power is approximately 5.4 W. The system features automatic data input synchronization with the recirculating CCD memory block start address. Descriptions are provided of both the buffer memory system and a custom tester that was used to exercise the memory. The testing procedures and testing results are discussed. Suggestions are provided for further development with regards to the utilization of advanced versions of CCD memory devices to both simplified and expanded memory system applications

An ICT image processing chip based on fast computation algorithm and self-timed circuit technique.

by Johnson, Tin-Chak Pang.Thesis (M.Phil.)--Chinese University of Hong Kong, 1997.Includes bibliographical references.AcknowledgmentsAbstractList of figuresList of tablesChapter 1. --- Introduction --- p.1-1Chapter 1.1 --- Introduction --- p.1-1Chapter 1.2 --- Introduction to asynchronous system --- p.1-5Chapter 1.2.1 --- Motivation --- p.1-5Chapter 1.2.2 --- Hazards --- p.1-7Chapter 1.2.3 --- Classes of Asynchronous circuits --- p.1-8Chapter 1.3 --- Introduction to Transform Coding --- p.1-9Chapter 1.4 --- Organization of the Thesis --- p.1-16Chapter 2. --- Asynchronous Design Methodologies --- p.2-1Chapter 2.1 --- Introduction --- p.2-1Chapter 2.2 --- Self-timed system --- p.2-2Chapter 2.3 --- DCVSL Methodology --- p.2-4Chapter 2.3.1 --- DCVSL gate --- p.2-5Chapter 2.3.2 --- Handshake Control --- p.2-7Chapter 2.4 --- Micropipeline Methodology --- p.2-11Chapter 2.4.1 --- Summary of previous design --- p.2-12Chapter 2.4.2 --- New Micropipeline structure and improvements --- p.2-17Chapter 2.4.2.1 --- Asymmetrical delay --- p.2-20Chapter 2.4.2.2 --- Variable Delay and Delay Value Selection --- p.2-22Chapter 2.5 --- Comparison between DCVSL and Micropipeline --- p.2-25Chapter 3. --- Self-timed Multipliers --- p.3-1Chapter 3.1 --- Introduction --- p.3-1Chapter 3.2 --- Design Example 1 : Bit-serial matrix multiplier --- p.3-3Chapter 3.2.1 --- DCVSL design --- p.3-4Chapter 3.2.2 --- Micropipeline design --- p.3-4Chapter 3.2.3 --- The first test chip --- p.3-5Chapter 3.2.4 --- Second test chip --- p.3-7Chapter 3.3 --- Design Example 2 - Modified Booth's Multiplier --- p.3-9Chapter 3.3.1 --- Circuit Design --- p.3-10Chapter 3.3.2 --- Simulation result --- p.3-12Chapter 3.3.3 --- The third test chip --- p.3-14Chapter 4. --- Current-Sensing Completion Detection --- p.4-1Chapter 4.1 --- Introduction --- p.4-1Chapter 4.2 --- Current-sensor --- p.4-2Chapter 4.2.1 --- Constant current source --- p.4-2Chapter 4.2.2 --- Current mirror --- p.4-4Chapter 4.2.3 --- Current comparator --- p.4-5Chapter 4.3 --- Self-timed logic using CSCD --- p.4-9Chapter 4.4 --- CSCD test chips and testing results --- p.4-10Chapter 4.4.1 --- Test result --- p.4-11Chapter 5. --- Self-timed ICT processor architecture --- p.5-1Chapter 5.1 --- Introduction --- p.5-1Chapter 5.2 --- Comparison of different architecture --- p.5-3Chapter 5.2.1 --- General purpose Digital Signal Processor --- p.5-5Chapter 5.2.1.1 --- Hardware and speed estimation : --- p.5-6Chapter 5.2.2 --- Micropipeline without fast algorithm --- p.5-7Chapter 5.2.2.1 --- Hardware and speed estimation : --- p.5-8Chapter 5.2.3 --- Micropipeline with fast algorithm (I) --- p.5-8Chapter 5.2.3.1 --- Hardware and speed estimation : --- p.5-9Chapter 5.2.4 --- Micropipeline with fast algorithm (II) --- p.5-10Chapter 5.2.4.1 --- Hardware and speed estimation : --- p.5-11Chapter 6. --- Implementation of self-timed ICT processor --- p.6-1Chapter 6.1 --- Introduction --- p.6-1Chapter 6.2 --- Implementation of Self-timed 2-D ICT processor (First version) --- p.6-3Chapter 6.2.1 --- 1-D ICT module --- p.6-4Chapter 6.2.2 --- Self-timed Transpose memory --- p.6-5Chapter 6.2.3 --- Layout Design --- p.6-8Chapter 6.3 --- Implementation of Self-timed 1-D ICT processor with fast algorithm (final version) --- p.6-9Chapter 6.3.1 --- I/O buffers and control units --- p.6-10Chapter 6.3.1.1 --- Input control --- p.6-11Chapter 6.3.1.2 --- Output control --- p.6-12Chapter 6.3.1.2.1 --- Self-timed Computational Block --- p.6-13Chapter 6.3.1.3 --- Handshake Control Unit --- p.6-14Chapter 6.3.1.4 --- Integer Execution Unit (IEU) --- p.6-18Chapter 6.3.1.5 --- Program memory and Instruction decoder --- p.6-20Chapter 6.3.2 --- Layout Design --- p.6-21Chapter 6.4 --- Specifications of the final version self-timed ICT chip --- p.6-22Chapter 7. --- Testing of Self-timed ICT processor --- p.7-1Chapter 7.1 --- Introduction --- p.7-1Chapter 7.2 --- Pin assignment of Self-timed 1 -D ICT chip --- p.7-2Chapter 7.3 --- Simulation --- p.7-3Chapter 7.4 --- Testing of Self-timed 1-D ICT processor --- p.7-5Chapter 7.4.1 --- Functional test --- p.7-5Chapter 7.4.1.1 --- Testing environment and results --- p.7-5Chapter 7.4.2 --- Transient Characteristics --- p.7-7Chapter 7.4.3 --- Comments on speed and power --- p.7-10Chapter 7.4.4 --- Determination of optimum delay control voltage --- p.7-12Chapter 7.5 --- Testing of delay element and other logic cells --- p.7-13Chapter 8. --- Conclusions --- p.8-1BibliographyAppendice