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CS1026 Digital Logic Design IICS1026 Digital Logic Design II

https://www.scss.tcd.ie/John.Waldron/cs1026/cs1026.htmlhttps://www.scss.tcd.ie/John.Waldron/cs1026/cs1026.html

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Digital Design, 5th EditionDigital Design, 5th Edition

By M. Morris Mano, By M. Morris Mano, Michael D. CilettiMichael D. Ciletti

Published by Prentice HallPublished by Prentice Hall

Copyright © 2013Copyright © 2013

Published Date: Jan 2, 2012Published Date: Jan 2, 2012

http://www.mypearsonstore.com/bookstore/http://www.mypearsonstore.com/bookstore/product.asp?isbn=0132774208product.asp?isbn=0132774208

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Bebop to the Boolean Boogie, Bebop to the Boolean Boogie, Third Edition: An Unconventional Guide Third Edition: An Unconventional Guide to Electronicsto Electronics

Also recommended, written in a more informal styleAlso recommended, written in a more informal style

Clive MaxfieldClive Maxfield

Publication Date: December 23, 2008 | ISBN-10: 1856175073 |Publication Date: December 23, 2008 | ISBN-10: 1856175073 | ISBN-13: 978-1856175074 | Edition: 3ISBN-13: 978-1856175074 | Edition: 3

The only electronics book in the world to include a Seafood Gumbo The only electronics book in the world to include a Seafood Gumbo reciperecipe

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Digital electronics represent Digital electronics represent signals by discrete bands of signals by discrete bands of analog levels, rather than by a analog levels, rather than by a continuous range. All levels continuous range. All levels within a band represent the within a band represent the same signal state. Relatively same signal state. Relatively small changes to the analog small changes to the analog signal levels due to manufacturing tolerance, signal attenuation signal levels due to manufacturing tolerance, signal attenuation or parasitic noise do not leave the discrete envelope, and as a or parasitic noise do not leave the discrete envelope, and as a result are ignored by signal state sensing circuitry.result are ignored by signal state sensing circuitry.

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ICs can be made very compact, ICs can be made very compact, having up to several billion having up to several billion transistors and other electronic transistors and other electronic components in an area the components in an area the size of a fingernail. size of a fingernail.

The transistor count of a device is the number of transistors in the device. The transistor count of a device is the number of transistors in the device. Transistor count is the most common measure of integrated circuit Transistor count is the most common measure of integrated circuit complexity. According to Moore's Law, the transistor count of thecomplexity. According to Moore's Law, the transistor count of theintegrated circuits doubles every two years. integrated circuits doubles every two years.

On most modern microprocessors, the majority of transistors are On most modern microprocessors, the majority of transistors are contained in caches.contained in caches.

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Inverter DelayInverter Delay

Pico is a unit prefix in the metric system denoting one trillionth, a factor of 10^−12 (0.000000000001). this was one of the original 12 prefixes defined in 1960 when the International System of Units was established.

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This amplifier circuit from Siemens was mass produced in 1965. This amplifier circuit from Siemens was mass produced in 1965. Containing three transistors and five resistors on a 1.5 mmContaining three transistors and five resistors on a 1.5 mm square chipsquare chip

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15-Core Xeon Ivy Bridge-EX, Transistor count = 4,310,000,00015-Core Xeon Ivy Bridge-EX, Transistor count = 4,310,000,00022 nm process, 23 mm x 23mm = 541 square mm22 nm process, 23 mm x 23mm = 541 square mm

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Lithography originally used an Lithography originally used an image drawn with oil, fat, or wax image drawn with oil, fat, or wax onto the surface of a smooth, level onto the surface of a smooth, level lithographic limestone plate. lithographic limestone plate.

The stone was treated with a The stone was treated with a mixture of acid and gum arabic,mixture of acid and gum arabic,etching the portions of the stone etching the portions of the stone which were not protected by the which were not protected by the grease-based image. grease-based image.

When the stone was subsequently moistened, these etched areas When the stone was subsequently moistened, these etched areas retained water; an oil-based ink could then be applied and would be retained water; an oil-based ink could then be applied and would be repelled by the water, sticking only to the original drawing.repelled by the water, sticking only to the original drawing.

LithographyLithography

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The word lithography comes from the Greek lithos, meaning stones, The word lithography comes from the Greek lithos, meaning stones, and graphia, meaning to write. It means quite literally writing on stones. and graphia, meaning to write. It means quite literally writing on stones.

In the case of semiconductor photolithography, In the case of semiconductor photolithography, our stones are silicon wafers and our patterns are our stones are silicon wafers and our patterns are written with a light-sensitive polymer called written with a light-sensitive polymer called photoresist. photoresist.

To build the complex structures that make up a To build the complex structures that make up a transistor and the many wires that connect the transistor and the many wires that connect the millions of transistors of a circuit, lithography millions of transistors of a circuit, lithography and pattern transfer steps are repeated at least 10 times, but more and pattern transfer steps are repeated at least 10 times, but more typically are done 20 to 30 times to make one circuit. typically are done 20 to 30 times to make one circuit.

Each pattern being printed on the wafer is aligned to the previously Each pattern being printed on the wafer is aligned to the previously formed patterns and slowly the conductors, insulators, and selectively formed patterns and slowly the conductors, insulators, and selectively doped regions are built up to form the final device.doped regions are built up to form the final device.

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Verilog HDL is a hardware description language used to design and Verilog HDL is a hardware description language used to design and document electronic systems. Verilog HDL allows designers to document electronic systems. Verilog HDL allows designers to design at various levels of abstraction. It is the most widely used design at various levels of abstraction. It is the most widely used HDL with a user community of more than 50,000 active designers. HDL with a user community of more than 50,000 active designers.

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Verilog is used in two waysVerilog is used in two ways

Model for discrete-event simulationModel for discrete-event simulation

Specification for a logic synthesis systemSpecification for a logic synthesis system

Logic synthesis converts a subset of the Verilog languageLogic synthesis converts a subset of the Verilog languageinto an efficient netlistinto an efficient netlist

One of the major breakthroughs in designing logic chips inOne of the major breakthroughs in designing logic chips inthe last 20 yearsthe last 20 years

Most chips are designed using at least some logicMost chips are designed using at least some logicsynthesissynthesis

Logic SynthesisLogic Synthesis

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Logic Synthesis ToolsLogic Synthesis Tools

Mostly commercial toolsMostly commercial tools• • Very difficult, complicated programs to write Very difficult, complicated programs to write wellwell• • Limited marketLimited market• • Commercial products in $10k – $100k price rangeCommercial products in $10k – $100k price rangeMajor vendorsMajor vendors• • Synopsys Design Compiler, FPGA ExpressSynopsys Design Compiler, FPGA Express• • Cadence BuildGatesCadence BuildGates• • Synplicity (FPGAs)Synplicity (FPGAs)• • Exemplar (FPGAs)Exemplar (FPGAs)Academic toolsAcademic tools••SIS (UC Berkeley)SIS (UC Berkeley)

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Synthesis and HDLs