Research...which one??

Hi Electro-Tech,
This might be a silly/vague question but all these components are just plain overwhelming!

How does a person narrow it down to a specific component they need to use for a particular project? There are thousands of components....its insane!!
I have only figured out what I need so far by luck, finding an example online or something. What if I cant find an example online or anywhere else?
I mean, I guess thats how people find out, by researching... but I want a more concrete way.
Is there even A WAY?? I kind of doubt it....but worth asking, right?

The datasheets dont have THAT much information on the components application and if it does, sometimes it doesnt make sense to me, the total newbie. And its not like I'm going to read the datasheets for every component in the category to find the right one...unless thats what I have to do.

So where do you start?
Is there a book that someone can recommend?

The only example that I have is this:
I found a tutorial:
**broken link removed**
I got a ULN2003 driver and the unipolar stepper motor. I plugged it in...it didnt work. I wasnt sure if I had it wired right, or if the ULN2003 just wasnt the right driver for my purpose. I wasnt doing the exact same thing as the tutorial so thats where my lack of confidence came into play. So it ended up that I didnt have the driver wired right, but for about 10+ hours I wasnt sure if I even had the right driver to begin with. So thats what I want to know. How do I KNOW for sure its the right component?

Thanks for being understanding of my total LACK of basic knowledge.
-MBE

Well I guess you figure out what you need it to do...and then your able to narrow it down to the right component.

I'm not sure a Stepper Motor is a wise first project.

I got it working though!!!

HOW do you narrow it down? Is there an electronics bible somewhere?

Bdoop21 said:

I got it working though!!!

HOW do you narrow it down? Is there an electronics bible somewhere?

Click to expand...

It's basically down to knowledge and experience, bear in mind if you use a special device it probably won't be available in 18 months!.

I guess so....and those 10+ hours of complete confusion will indeed happen again and again...
but its cool stuff

As Niegl posted it's mostly experience and of course the basic training/knowledge/study in electronics.

Take simple resistors, there are thousands to choose from. But from experience you will know what specifications are important to the design you have such as wattage, tolerance, package type. Same with capacitors and simple semiconductor diodes and transistors.

When you get to ICs it's a little more difficult but same principles apply. Simple logic and op amp chips can be picked from many equivalent model numbers. Specialty chips are more a function of reading their data sheets and seeing if they are applicable to your design or if your design can be modified to use them.

Lefty

Don't over research, more time should be spent experimenting. It might be more expensive but it teaches better in the end.

I tend to pick a company for a group of parts and try to get all those parts from that same company.

THe company tends to get picked by their quality of documentation or how easy it is to navigate through all their components on their website. Oh...availability too!

Hi M,

I think that as Lefty said, it usually winds up being a case of defining what you want and looking up something which fits well enough, even if you have to juggle things to make it work. It's also a matter of remembering which are the important items in a datasheet--and that will depend on what you want the part to do. Say you're running your circuit on 5VDC. Right there that narrows the field of what you need for, say, an opamp. You only need to look at the ones that will work at that voltage. Or if you're working on an audio preamp, look for an opamp which works well with the bandwidth you want.

Also, ask for opinions on parts. You'll get them.


Torben

There are countless electronics courses or tutorials available - books, video format, on-line and of course in-person (local universities, amateur radio or other hobby organizations). They provide some structure and order to things. Jameco and other electronics companies used to (and probably still do) sell electronics kits that include a breadboard, components and lessons. Unfortunately there's an amount of study involved just to get to a point where you start to see how much you don't know. What many do is have a specific interest in mind - robotics, audio, microcontrollers, amateur radio, RC modelling, etc - then look within those areas to find tutorials or books on the basics. This approach might enable you to have more fun by getting your hands on something sooner.

As far as component selection - you might check electronics books, magazines and other publications. You'll start to see some common parts. Transistors that I see frequently used - 2N3904, 2N2222A, MPF102, 2N3055. Someone here might have a little better list - but usually you'll find these available from places like Jameco at modest cost. As you say, there are thousands to choose from. Mfr's data is aimed at folks who can easily interpret the information - not the hobbyist.

Thank you all for responding! Great advise.

I started off by taking apart old electronics and then looking them up online. Then I looked for projects to use them in. Now that I have experience, I do things the other way around and come up with the idea first, parts list later.

It may be easier if you first identify the major component in an ideas solution. Then all the other parts are usually figured out once you find out what the major part can do and what supporting components it needs.

I started taking old electronics apart, and looking the functions up in the 1954 edition of the Radio Amateur's Handbook (Now the ARRL Handbook). Probably the best resource for me was the massive tube table in the back. When transistors began to get popular, I got data books from RCA and GE, and subscribed to Electronics Illustrated and then Popular Electronics. Shortly after integrated circuits were invented, I got more RCA data books, and later I subscribed to BYTE. (It was a computer hardware magazine back then.)

The following circuit applet can save you a lot of money on fried parts.
Try building it here first and get the power readings.
Then you will know what part values you need.
https://www.falstad.com/circuit/