Digital Systems Design with FPGAs and CPLDs

Ian Grout

• Publisher: Newnes
• Year: 2011
• Print ISBN: 9780750683975
• eBook ISBN: 9780080558509
• Topic: Computer Science
• Subtopic: Hardware
• Index: Computer Science

Digital Systems Design with FPGAs and CPLDs explains how to design and develop digital electronic systems using programmable logic devices (PLDs). Totally practical in nature, the book features numerous (quantify when known) case study designs using a variety of Field Programmable Gate Array (FPGA) and Complex Programmable Logic Devices (CPLD), for a range of applications from control and instrumentation to semiconductor automatic test equipment.Key features include: * Case studies that provide a walk through of the design process, highlighting the trade-offs involved.* Discussion of real world issues such as choice of device, pin-out, power supply, power supply decoupling, signal integrity- for embedding FPGAs within a PCB based design.With this book engineers will be able to: * Use PLD technology to develop digital and mixed signal electronic systems* Develop PLD based designs using both schematic capture and VHDL synthesis techniques* Interface a PLD to digital and mixed-signal systems* Undertake complete design exercises from design concept through to the build and test of PLD based electronic hardwareThis book will be ideal for electronic and computer engineering students taking a practical or Lab based course on digital systems development using PLDs and for engineers in industry looking for concrete advice on developing a digital system using a FPGA or CPLD as its core.- Case studies that provide a walk through of the design process, highlighting the trade-offs involved.- Discussion of real world issues such as choice of device, pin-out, power supply, power supply decoupling, signal integrity- for embedding FPGAs within a PCB based design.

CHAPTER 1 Introduction to Programmable Logic

1.1 Introduction to the Book

Increasingly, electronic circuits and systems are being designed using technologies that offer rapid prototyping, programmability, and re-use (reprogrammability and component recycling) capabilities to allow a system product to be developed in a minimal time, to allow in-service reconfiguration (for normal product upgrading to improve performance, to provide design debugging capabilities, and for the inevitable requirement for design bug removal), or even to recycle the electronic components for another application. These aspects are required by the reduced time-to-market and increased complexities for applications—from mobile phones through computer and control, instrumentation, and test applications. So, how can this be achieved using the range of electronic circuit technologies available today? Several avenues are open. The main focus of developing electronics with the above capabilities has been in the digital domain because the design techniques and nature of the digital signals are well suited to reconfiguration.

In the digital domain, the choice of implementation technology is essentially whether to use dedicated (and fixed) functionality digital logic, to use a software-programmed, processor-based system (designed based on a microprocessor, µP; microcontroller, µC; or digital signal processor, DSP), or to use a hardware-configured programmable logic device (PLD), whether simple (SPLD), complex (CPLD), or the field programmable gate array (FPGA). Memory used for the storage of data and program code is integral to many digital circuits and systems. The choices are shown in Figure 1.1.

Figure 1.1 Technology choices for digital circuit design

In Figure 1.1, the electronic components used are integrated circuits (ICs). These are electronic circuits packaged within a suitable housing that contain complete circuits ranging from a few dozen transistors to hundreds of millions of transistors, the complexity of the circuit depending on the designed functionality. Examples of packaged ICs are shown in Figure 1.2.

Figure 1.2 Examples of IC packages with the tops removed and the silicon dies exposed

In many circuits, the underlying technology will be based on IC, and a complete electronic circuit will consist of a number of ICs, together with other circuit components such as resistors and capacitors. In this book, the generic word technology will be used throughout. The Oxford Dictionary of English defines technology as “the application of scientific knowledge for practical purposes, especially in industry” [1].

For us, this applies to the underlying electronic hardware and software that can be used to design a circuit for a given requirement. For the arrangement identified in Figure 1.1, a given set of digital circuit requirements are developed, and the role of the designer is to come up with a solution that meets ideally all of the requirements. Typical requirements include:

• Cost restraints: The design process, the cost of components, the manufacturing costs, and the maintenance and future development costs must be within specific limits.

• Design time: The design must be generated within a certain time limit.

• Component supply: The designer might have a free hand in choosing the components to use, or restrictions may be set by the company or project management requirements.

• Prior experience: The designer may have prior experience in using a particular technology, which might or might not be suitable to the current design.

• Training: The designer might require specific training to utilize a specific technology if he or she does not have the necessary prior experience.

• Contract arrangements: If the design is to be created for a specific customer, the customer would typically provide a set of constraints that would be set down in the design contract.

• Size/volume constraints: the design would need to be manufactured to fit into a specific size/volume,

• Weight constraints: the design would need to be manufactured to be within specific weight restrictions (e.g. for portable applications such as mobile phones),

• Power source: the electronic product would be either fixed (in a single location so allowing for the use of a fixed power source) or portable (to be carried to multiple places requiring a portable power source (such as battery or solar cell),

• Power consumption constraints: The power consumption should be as low as possible in order to (i) minimise the power source requirements, (ii) be operable for a specific time on a limited power source, and (iii) be compatible with best practice in the development of electronic products that are conscious of environmental issues.

The initial choice for implementing the digital circuit is between a standard product IC and an ASIC (application-specific integrated circuit) [2]:

• Standard product IC: This is an off-the-shelf electronic component that has been designed and manufactured by a company for a given purpose, or range of use, and that is commercially available for others to use. These would be purchased either from a component supplier or directly from the designer or manufact...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• system
• Preface
• Abbreviations
• Chapter 1: Introduction to Programmable Logic
• Chapter 2: Electronic Systems Design
• Chapter 3: PCB Design
• Chapter 4: Design Languages
• Chapter 5: Introduction to Digital Logic Design
• Chapter 6: Introduction to Digital Logic Design with VHDL
• Chapter 7: Introduction to Digital Signal Processing
• Chapter 8: Interfacing Digital Logic to the Real World: A/D Conversion, D/A Conversion, and Power Electronics
• Chapter 9: Testing the Electronic System
• Chapter 10: System-Level Design
• Additional References
• Index