Usage of SMD elements

Forum 2005-2010 (read only) General Frequently-Asked Questions
1

Good day!

For now I'm soldering my circuits on a perfboard with 2.54mm holes. Can I get any benefits from using elements in SMD cases?

My near plans are to make some simple PCB at home using some free CAD software, should I consider SMD elements for this (minimal holes to drill in DIY PCB any other benefits)?

Thanks in advance!

2

minimal holes to drill in DIY PCB any other benefits

I've found this to be a tremendous benefit of SMT when fabricating boards at home. Drilling holes is time consuming.

-j

3

Thanks for the response, what software do you use, what method of making PCBs? Have you using MCU in SOIC or TFQP cases?

4

Depends what MCU, I think, but the PCB's I've made have used AVR 1280's in TQFP packages.

5

What technology do you use to make PCB at home?

6

I use the free version of Eagle. Bit of a learning curve, plenty powerful, and runs on a mac.

I've used Press-n-peel toner transfer, and etched with HCl and peroxide. I prefer HCl/H2O2 for the etchant because it's quite effective, not annoying like FeCl (which is endothermic, needs heat sometimes, is opaque, and needs to be handled carefully to avoid plumbing damage), and the chemicals are available locally, even in small towns ("brick acid" at the hardware store, peroxide at the drug store or grocery).

SOIC, TQFP (which is like a 4 sided SOIC), SOT-23, 1206, 0804, and 0603 (those last two may need some solder paste and hot air instead of an iron), QSSOP (pain with an iron, but doable).

-j

7

Thanks for the details, that's a good starting point for me!

8

I use a product by abacom for my PCB drawing. Not free... but real easy to use and accurate. Ideal for HOBBY use. It's Sprint Layout. I Do SMD stuff all the time.

http://www.abacom-online.de/uk/html/sprint-layout.html

I also use kg4wsv's method of fabrication with excellent results. I use a thermal laminator to apply the toner.

9

I use photo-etch to make my boards, with pre-coated board material in a home-made UV exposure unit. Transparencies are printed on a cheap inkjet printer. Results are excellent - tracks down to 8 mil or less.

The Yahoo Homebrew PCB group is very useful.

10

Thanks for the responses, it seems I will try something on Holidays :slight_smile:

11

I often use surface mount parts with strip board, see my projects:-
http://www.thebox.myzen.co.uk/Hardware/Mini_Monome.html
and the others on the site.

They are very good for decoupling as you can get the components right on the package leads without the lead wire inductance of a leaded component. Also some parts are only available in surface mount. Finally they can save space.

12

Thanks, Mike, it seems I'll use at least SMD capacitors for decoupling on a perfboard.

Any advices about which type (size) of SMD to choose?