Slashdot Mirror
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?"
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
Oolite: Elite-like game. For Mac, Linux and Windows
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?
Rocky's Boots kicks ass. Extremely clever, very educational, and like everything the author did, way ahead of its time. Created by the Easter Egg inventor and game developer legend Warren Robinett.
+0 Meh
...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).
Oolite: Elite-like game. For Mac, Linux and Windows
I loved that game! But now it's nearly unavailable, and hard to get running at all. Is there any PC remake or independent spinoff of it out there?
You can download the DOS version at HotU, which runs just fine in Bochs or DosBox.
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.
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=
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.