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Methods of Learning to Build Electronic Circuitry?
Peristaltic asks: "I've seen some cool articles in Instructables detailing how to create various electronic gadgets. A couple of these as well as the odd DIY kit have come to life on my kitchen table. While it's satisfying to see the things work after time spent soldering, I would love to be able to take the next step beyond the basics of component functionality, i.e. a resistor does -this-; a capacitor does -that-. Forest Mimm's books have been helpful towards this end, but it's time to move forward. Every month or so, I read here on Slashdot a plea for help getting started with, or expanding someone's knowledge of programming. OK, I'd like to make that plea for help with electronics theory & circuit building. I've found plenty of references on the web, Amazon, etc., but can someone who's already taken this trip outline what has and hasn't worked for them?"
...Rocky's Boots - my 4 year old knew more about feedback circuits than 1/2 the engineering students in the local college.
I tinkered with electronics & "Radio-Shack" projects back in the late 1970s & early '80s and I still like to go into the local electronics stores to look around (note: NOT Radio Shack anymore). You used to be able to feel like you were doing something close to useful when you breadboarded that 555 IC alarm system, 2N222 transistor amp or got a simple 74xxx "ALU" to work, but nowadays in the 100MHz+ world (yes, I come from the days when computers ran at 5Mhz=0.005Ghz!) it is tough to tinker with anything that has any power.
The Basic Stamp kits look good. You seem to need a pretty hefty Oscilliscope nowadays also.
I would suggest taking the training for a Amature ("HAM") radio license since that involves all the basic electronics stuff, then move into more digital stuff.
TDz.
A Radio Shack 150-in-1 kit worked for me in the 70s. But given how far that place has gone downhill since that time, I would be surprised if a single employee knows his ohms and farads.
Buy The Art of Electronics by Paul Horowitz and Winfield Hill and also buy the lab manual. Follow through each experiment from beginning to end and you will have a very strong intuitive sense on how to design simple electronic circuits. This would be more than enough for most hobbyists (and some professionals in associated fields), but you could always just get a EE degree if you want to go further.
As an aside, the Art of Electronics book doesn't go into extreme depth on I&CE so you might want to buy some other books for that.
Horowitz and Hill: The art of electronics.
This book is pretty much the bible for Electronic Engineers, myself included. Takes you from the basics (a resistor does this etc.) as you requested up to high level stuff. Its in a pretty understandable language, and gives good examples, both of good practice and bad practice.
A good step to take would also be to familiarise yourself with a basic microprocessor too, My favourite being the venerable Microchip PIC. Good dev kits to play with for these are £100, such as the USB based PICDEM FS USB (£30), which uses the PIC18F4550, and is preloaded with a bootloader, so no need for any external programmers. Along with a good breadboard kit you could use this to produce some pretty powerful designs.
Also remember that many IC manufacturers have sampling options which for a private tinkerer like yourself you will find invaluable! Please do not abuse this system and spoil it for the rest of us though!
Experiment. Really.
I started with electronics properly in about September time. Probably the most valuable parts I have in terms of experimentation:
1. A large breadboard (the plug in type). This means you can rapidly try things out. I now have two breadboards - one small, and one large.
2. An oscilloscope. I bought a dual trace 20MHz Gould scope off an eBayer. I would have been lost without it. The dual trace is very useful too when you need to compare signals or check that things are synchronized.
3. The Internet. Seriously - some good resources:
http://www.ibiblio.org/kuphaldt/electricCircuits/ - Lessons in Electric Circuits, a free book - will get you started.
http://www.standardics.nxp.com/products/ Datasheets for every standard logic IC (4000 series and 74 series). Browse the site for chips you're interested in. They are cheap to buy from your local distributor (in Britain, you've got several choices - RS components, Maplin (a bit on the expensive side, but very fast delivery), Bowood Electronics (a superb small firm, fast delivery), Farnell (not used them yet, but they have an extensive catalogue).
http://www.wikipedia.org/ Lots of good articles. I used their article on buck and boost converters to get started on making high voltage switch mode power supplies for my first proper project.
The first thing I did on my breadboard was make simple circuits and understand them - using the versatile 555 timer, making logic gates out of discrete components, making an oscillator from transistors, capacitors and resistors. Then learned about how inductors work - how to use a small inductor to make a DC-DC converter. Comparing how bipolar transistors and MOSFETs work. Making small practical circuits like pulse generators etc. Then using logic ICs
I then built a Nixie tube display (with 7 tubes) out of raw 4000 series logic - essentially, I designed and built my own UART to receive data from a computer's RS232 port and display it on the tubes, and to be able to send data back to select what to display on the tubes. (Two pages of pictures here: http://www.alioth.net/pics/nixies/nixies.html). The nixie tube project was a great one to do as I had to learn lots of different things to be able to make it work: how to make a 170 volt switch mode power supply to the use of digital logic and how to debounce switches.
Now I've started designing and building an 8 bit computer based around the Z80, with flash ROM and static RAM plus an LCD interface etc. It actually works, too - I've got it running off a 4MHz crystal oscillator that I built. There's still a lot to learn - but I've gone from having very little knowledge of how to build electronic circuits to designing and building a simple 8 bit computer (with a keypad for input and LCD for output) in just a few months - if you're already experienced with software, learning about digital electronics is fairly natural. I can really recommend building something reasonably complex out of discrete 4000 or 74 series parts, because this is a great vehicle for learning about digital electronics, and how the real world tends to impinge on you a lot more than it does with software.
Pictures of the rat's nest of wiring that's the Z80 project is here (I've not updated it in a few weeks, I have more photos and assembler code to go in soon): http://www.alioth.net/Projects/Z80/
Why the Z80? Unlike all other processors, the Z80 has registers implemented in static memory. This means when you're experimenting, you can clock the processor arbitrarily slowly - fractions of 1Hz if you really want (or even clock it by hand). This makes early circuits A LOT easier to debug. It's not hard to program, has superb documentation free to download from Zilog. It has separate I/O
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Well, this will take time, so as long as you keep that in mind...
Resource books:
ARRL Handbook
The Art of Electronics by Horowitz and Hill
App notes from manufacturers in current interest areas
Freebie design software ( I like Altera, Analog Devices, Atmel )
Digikey catalog
Design tools:
In System Programmers's for current part interests
Assemblers, compilers, etc.
Evaluation boards for the multileaded surface mount parts ie DSP's etc.
Some PCB layout package (on linux) or web tool
Prototyping board - which is good for low frequencies
Stock up on full set of resistors 1/4 w 10 pcs per value
Caps and inductors are tricky - so you might want to buy them carefully
Good soldering station - when you get to surface mount you can thank me...
Roadmap:
Transistor diode circuits are easy, and you can analyse them by the ideal diode equation and ohms law.
Your Favorite Micro Family Here I've used Motorola(now freescale), intel, zilog, and atmel
DSP's? I've used Analog Devices, TI, and Freescale. Software tool availability and eval boards are key.
Analog circuitry has a long learning curve so I'll add to this thread later.
This is progress?
The first thing is probably to define what you want to do more specifically, i.e. what kind of electronic gadget you want to build. Try not to pick something that isn't too hard. Then you look at what other people have built and try to understand their solutions. After that you try to tweak their solutions (adding/changing stuff here and there). Repeat and rinse a few times and before you know it you'll be building your own things.
Depending on how sophisticated your education needs get, "Electronic Circuits" by Tietze and Schenk may be worthwile:k -Design-Application/dp/3540004297/sr=8-1/qid=11685 10366/ref=pd_bbs_sr_1/105-9488728-1526850?ie=UTF8& s=books ;-) more scientific.
http://www.amazon.com/Electronic-Circuits-Handboo
It is a college-level textbook that focuses on the application of electronic circuits. Some advanced mathematics are required, but usually the modelling is on the simple side rather than trying to capture all the fine details.
Overall I consider it a highly useful book for designing everyday electronics. People who are working on cutting-edge technology might want something (even
C - the footgun of programming languages
I currently have an 8 bit computer breadboarded - Z80 CPU, 32K RAM, 128K flash ROM, PIO, LCD interface and keypad. Breadboarding is practical for any IC you can get in DIL packages. I'm still learning, and there are plenty of fairly complex circuits you can make on breadboard (even if they do look like a rats nest).
0 -Project-Pages/Image4.html
Most things are still available in DIL packages - the Z80 CPU and its peripheral chips are *still manufactured* in that form. Static RAM and flash ROM is easy to get hold of in DIL packages. Of course, there are mountains of 74-series and 4000-series logic and other things like 555 timers made in their tens of millions.
Here is my current rat's nest: http://www.alioth.net/Projects/Z80/Z80-Project/Z8
You probably don't want to start learning and experimenting directly with 100 pin QFPs. It would be an exercise in futility.
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No, I'm not kidding. Find a good school and go. You'll get tons of theory, and lots of hands on experience, and the opportunity to work on amazing projects with incredibly smart people. If you're really keen on it, that's what I suggest.
Why do you need to tinker with anything that has "power"? A Z80 CPU is still as good today as it was 20 years ago (and they are still made - they are popular in embedded applications, which was after all what they were originally designed for). You can make plenty of useful devices with a 4MHz PIC or a 4MHz Z80. If you're making embedded computers, they simply don't NEED the power of a modern desktop CPU. I think people forget this and get dragged on with the marketing myth that everything needs a 1GHz+ processor when it simply doesn't. A 4MHz Z80 will still barely work up a sweat as part of say, a logging weather station. Which is a good thing because you want the battery to last.
74 series and 4000 series logic, 555 timers and the like are STILL as much fun to play with as they were 20 years ago. The existence of 3.6 GHz Xeon processors does not reduce the amount of learning or fun you can have from these parts, nor does it make simple parts any less useful than they ever were. You can still make useful gadgets with simple parts, and it's not hard to interface them with a modern desktop computer if need be.
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Lots of suppliers and circuits
http://www.makezine.com/
Lots of suppliers and circuits
http://www.nutsvolts.com/
Online textbook
http://www.allaboutcircuits.com/
Forum
http://forum.allaboutcircuits.com/index.php
I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
Also, decide early on if you want to get into analogue circuitry or if you're more interested in digital. It's two different worlds which ain't got much in common. The trend is that more and more circuits are digital. Even if the end-output or the inputs are analogue, that's often converted to/from digital and the rest done digitally.
...oh, an observation: I've only just started to make my own PCBs, but *don't* print a mirror image of the solder side if you want it to be on the *bottom* of the board (although this might depend on the tool you're using). When you view your printed output from above, this would be like viewing the board from above with the copper bottom most (imagine if the board was transparent). The bottom side must be printed true image, and the top side mirror image.
This caught me out with my first board because without thinking I thought "of course I need to mirror image it".
Secondly, when learning, I think starting out with breadboard is a lot more productive than jumping straight in with PCBs! However, when it comes to making a PCB (I've now used strip board, tri pad board, and finally I've started making PCBs), a PCB is SO MUCH MORE FUN and easier to do than strip board, which is evil. The cheap glossy photo paper and laser printer method works *unbelivably well*. I couldn't believe just how well the toner transferred to the copper clad board, and how precise the traces were - if you covered it in a green solder resist layer it would have looked like it came from a factory.
Using IC sockets will help avoid frying ICs (and also makes the board easy to fix when one of your experiments accidentally puts a few too many volts where they shouldn't be).
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I've just completed a electrical engineering degree, and I can't stress how important the fundamentals are. This online book got me through the first 2 years of my degree:
http://www.allaboutcircuits.com/
Knowing exactly what each component does, and what effect it has when combined with other components is paramount to understanding more complex circuitry. Even in a digital system there is a chuck of analogue stuff which will really confuse you if you don't know what it does (and whether it affects the operation of the digital part).
Apart from the basics, the rest is all exposure really. Finding out how some effect is created, what techniques they've used, why they work the way they do, you'll learn all of this as you are exposed to more and more circuitry. You will definitely get overwhelmed if you try and learn everything though. For basic exposure an undergrad introduction textbook will serve you fine, once through that find out what your really interested in and read the recommended textbooks from any university.
Just fyi, in my electrical degree there are about 5 streams which you can specialise in, each which take about 2 years of concentrated study. And that's just at undergraduate level! (I'm in australia and our university system is different to that of the US, an undergrad ee degree is 4 years straight out of high school)
If you can't find it in a DIL (or DIP) then digkeyhttp://www.digikey.com/scripts/DkSearch/dksu s.dll?Criteria?Ref=33490&Site=US&Cat=34079261 sells adapters. Many manufactures will also send you a few samples of chips for development work, they generally send you ~5 of any sub $15 chip for free (including shipping). Maximhttp://www.maxim-ic.com/ is one of the best for sending out free samples quickly, but analog deviceshttp://www.analog.com/, and just about any of the others send out freebees as well.
The 8051 is still around too, and is still under active development. No more eprom programmers & UV erase lamps. They have 1 clock cores now, where 20Mhz = 20 MIPS. You can program them with a parallel port dongle. Some of the advanced ones program via a bootloader ROM. The AT89C51ED2... Hold reset, tap PSEN, release reset, and talk to it via the serial port. Atmel FLIP is available for Linux. GPL SDCC for C afectionados.
The Intel MCS-52 BASIC is available from numerous sites, one of which has enhanced it to work on a modern chip with internal RAM (like the above mentioned ED2). In 12 cycle mode, it can run 60Mhz. Try that with a Basic Stamp!
Then there's the AVR's. Better arch for C compilers, but single source.
Avoid PIC's. Their arch is straight from the mid 1970's. Not orthoganal at all, oddball word sizes, instruction extensions, and 10,000 different chips to choose form.
You forgot another reason why these older devices are worth serious consideration: Cost.
A Z80 is not only likely to be powerful enough for your project, it's also dirt cheap (About $5 each.) A Motorola 68K will cost under $15. Of course, there are modern variations with some extra features, so price for a specific sub-breed may vary.
I'm a fan of the 8051-decended microcontrollers, since they greatly reduce the number of support components (on-chip oscillator circuits). Flash based EEPROM units go for about $7 each or less, can be clocked at anything between 0Hz - 24MHz, and come with a plethera of features depending on model: integrated A/D & D/A converters, USB host interfaces and PWM generators being popular.
You definately do not need a $300, 150-million-transistor space heater for most embedded applications.
=Smidge=
I completely agree, there's nothing wrong with simpler chips, there's no real need for 100Mhz+ devices in your projects unless it calls for them. You don't pick some high speed piece of kit and thinking of something to do with it (that's a totally wrong approach IMO). You should be thinking of an application and then build the circuit to fit your application. You need to find a problem and develop a solution, not have a solution and try to find a problem it might fix. Choosing to use simple through hole logic circuits, or microcontrollers as opposed to modern high speed surface mount devices should be a decision you make based on the problem you're trying to solve... and there are quite a few problems that can be solved with simple circuits.
To the OP: As someone who has already gone down that road (from following pre-planed projects to building my own custom stuff)... There is just one simple factor to do...
Decide what you want to do (define your "problem) and then build it (develop the "solution").
Today I basically have an idea for something I want to build, and then I begin figuring how I can accomplish that using the individual part data, usually from simple chips like 74XXX and 555s to more complex chips like Basic STAMP and PIC chips. Most often I choose projects that I feel are just a hair out of my range and I learn some new skills along the way.
I've been working on many little projects but my last BIG project was an adapter that allowed you to use a Sega Saturn controller on an Xbox 360. I had limited microcontroller experience so I learned about them, figured out which one would best suit my needs, and costs, and then I learned the assembly language used to program it. I also learned a lot about multiplexers (and why they wouldn't work for what I was trying to do). But that project like many others weren't following any kind of guide, and they weren't based on something someone else had already done. I find developing a circuit similar to piecing together a puzzle, you have an idea if which pieces might fit where and you might have a few holes in your design and then hunt around for pieces that might fit that you didn't know about, expanding your knowledge along the way.
Basically just learning what the function, capabilities, and limits of number of electronic components do is the first step. Once you have those in your pocket you can start to utilize them for something unique. Like the words of a foreign language... now all you have to do is think of something creative to say. It's not anything you'll learn from a book, because the next step is be creative and think of something to build.
Collector's Edition
While many solders out there do not contain lead, most do; even the ones that don't contain lead have flux which is pretty unhealthy.
So, don't solder on your kitchen table. And always always always wash your hands after you solder.
Comedy is Tragedy that happens to others.
There are "capital F" Free electronics design tools - I use GNU PCB and gSchem on Linux. The two can be linked together to produce PCBs from schematics. It isn't tied to a particular PCB fabricator - indeed, I've just started fabricating my own PCBs at home.
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The fastest, most intricate wire-wrap board I recall seeing was a prototype of the first Apple PowerPC based computer. I forgot the title of the movie it was in, maybe someone here remembers?. The complexity of it was jaw dropping, I never knew you could do something so complex and fast with wire-wrapping.
This book was based off the one-semester course Physics 123 taught at Harvard. In the course itself, which is taken by people of all majors, you design and build all kinds of things like radio receiver and transmitters, amps, filters, and after maybe 4-5 weeks you actually design and build a circuit to take an audio signal, figure out a way to transmit it via infrared diodes, receive it with infrared photodiodes across the room, and rebuild the audio structure and play back on a speaker. This was satisfactorily done in the class by psychology majors with absolutely no prior electronic or much physics background. If they can do it, you can.
The second half of the book (and the course) is digital electronics, culminating in the building of a 68008 digital computer with a motherboard-based breadboard. People have gone on to add things such as putting two DACs and feeding the output to an oscilloscope to draw pictures, and programming the CPU to make a PacMan game, for example. Really wild stuff.
The book is awsome, it starts with resistors, then capacitors, and goes on to transistors, and then op-amps, going from ideal to real-world structures. And you really only need some high-school level algebra to follow it. The reading is not dry at all, the authors actually make it interesting to read.
The only criticism I ever heard about this book was by a guy with a masters in Electrical Engineering who commented that one of their circuits wouldn't work in the high-Megahertz range and was a faulty design, and said much of their stuff isn't high-end design. This guy has a masters degree, and spent 6 years of education taking advanced EE courses, so if that's his critique of the book then you can bet that for people trying to go from nothing to complicated systems it's a great book.
make world, not war
Uh, yeah. Microcontrollers != electronics. Not even close. Yeah, you can be another guy making magic 8-balls with stamps (they can't really do much more than that). Electronics is much more than that, and it honestly sounds like you don't have much of a clue. There is a lot of fun you can have with analog electronics, FPGAs, real microprocessors, and various application-specific chips. Building a simple op-amp headphone amp and understanding how it works and how to improve it is a much better learning experience.
I would start with "The Art of Electronics" by Horowitz and Hill. Jim Williams' book is pretty good reading, too (Art of analog design or something like that). If you like audio amplifiers, Douglas Self's books are absolutely awesome. In my opinion, digital design is a skill while high performance analog is an art (much more interesting and far more difficult). Of course, any engineer or serious hobbyist should be able to do both well.
If you like microcontrollers, get a digital logic textbook and learn what is inside first. Anyone who writes stuff for microcontrollers should have no trouble drawing a detailed block diagram of one. You should be able to learn to program any given 8-bit chip in a couple of days, whether it's a PIC, 8051, AVR, Z80, 68HC11, or your own design. I am pretty sure most basic stamp developers don't even know what a finite state machine is. Hence, their mortal fear of assembly or machine code. Learning electronics with basic stamps is like learning to swim in a bathtub. Not to mention, the whole point of an 8-bit microcontroller is that it's extremely cheap. Even a moderately complicated robot might have dozens of them. Paying $50 a pop defeats the point.