Digital Electronics

Test On Digital Electronics Applications Do not refer to the text when taking this test. You may draw diagrams or use a calculator if necessary. A good score is at least 38 correct answers. Answers are in the back of the book. It’s best to have a friend check your score the first time so […]
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Synchronous Serial Interfaces (SPI, I2C, Microwire) There are two very common synchronous data protocols, Microwire and SPI, from which a variety of standard devices (memory and peripheral functions) have been designed around, including serial EEPROMs, sensors and other I/O functions. I consider these protocols to be methods of transferring synchronous serial data rather than intelligent […]
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PC Interfacing Basics From a practical point of view, chances are you will be designing an interface or enhancement to your PC. Most modern commercial devices utilize USB ports, but you can still do a lot of interesting projects with the ‘‘legacy’’ interfaces built into the PC. Along with this, a basic understanding of your […]
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Power Supplies It is surprising to many people that you can add a simple voltage regulator to power your projects for just a few dollars; cheaper than a set of rechargeable batteries. Voltage regulators, powered by an AC/DC ‘‘Wall wart’’ power converter, will convert one DC voltage to another that can be used by the […]
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Computer Processors and Support I’m sure that you realize that computer processors are really just a great big sequential circuit, but I’m sure that you have no idea where to start understanding how they work. Traditional computer processors are designed using a selection of six or so basic design philosophies that give them different characteristics. […]
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Reading Datasheets I’ve never understood why college and university courses do not give an introductory course in reading digital electronic device datasheets. Despite how prepared you are for them, you will feel quite overwhelmed the first time you have to look through a number of datasheets trying to find a part that meets your requirements. […]
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Pulse Width Modulation Despite showing how logic gates and other digital devices are built from simple analog components, they do not handle working with analog voltages very well. There are some circuits that will produce a valid analog (an arbitrary voltage, not just logic ‘‘high’’ and ‘‘low’’) voltage but they do not work very well […]
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Circuit Interfaces For a sequential digital electronic circuit to be effective, it has to interface with something. This something could be a person or it could be other digital electronic circuits. If you were to look at different interfaces for either case (human or machine), you will discover that as the function of the circuit […]
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Linear Feedback Shift Registers One of the most interesting logic devices you can work with is the ‘‘linear feedback shift register’’ (‘‘LFSR’’). It is built from a shift register along with two or more XOR gates modifying the contents of the register as shown in Fig. 9-12. This circuit can be used to ‘‘pseudo-randomize’’ data, […]
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Complex Sequential Circuits As the saying goes: ‘‘You now know enough to be dangerous.’’ You should be fairly comfortable with working with logic functions and equations, have an understanding of electronics and how to interface logic chips (of different families together), understand the basics of memory and have gone through a number of clocking schemes. […]
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