added bonus that much of the component’s supporting
circuitry (resistors, capacitors, etc.) is included. It’s also
possible to buy an adapter board and solder the SM
component to it yourself. Several companies (like
SchmartBoard) specialize in adapter boards of all sizes and
pitches (lead spacing).
Now, you could use an SM component on an adapter
board for your final configuration, but wouldn’t the best
practice be to just create a PCB and solder everything
together without adapters? Creating your own PCB might
sound daunting, but the rewards are more than worth
the effort. Getting Started With Making Your Own PCBs
There is a dizzying array of PCB configurations and
ways to make them. This article will walk you through the
general process of:
1. Selecting and using a computer aided drafting
program (CAD) to design your circuit.
2. Ordering boards from a board house of your choice.
3. Ordering the solder paste stencil at a company of
your choice.
4. Applying the solder paste and placing the SM
components.
5. Soldering the board using a toaster oven.
By the end of this article, you should be able to build
on your previous experience creating circuits with
breadboards and know the basics of making your own
PCBs. We’re not going to be able to go into all of the
details — such as how to use the CAD software — because
you might want to use a different program, and each
program has an excellent tutorial.
A word about safety: Please be careful! Read and
follow all safety directions. Always wear and use
appropriate safety equipment. I personally wear safety
glasses and rubber gloves whenever I’m working with lead-based solder paste and will only solder in a well-ventilated
area to avoid the fumes. If you’re unsure, please consult the
manufacturer or board house before beginning. You alone
are responsible for your safety. Designing Your Circuit Board
There are many different CAD programs that you can
use for designing your circuit board layout. Sometimes they
are abbreviated as eCAD to differentiate them from a
mechanical CAD (mCAD) program that might be used to
design a 3D part.
A quick Internet search will give you a list of numerous
programs — free or available for purchase. I would
recommend that you “try before you buy” and make sure
that the software package allows you to create patterns,
components, and export the Gerber/NC Drill files. Gerber
files are the (nearly) universal file format that circuit board
houses use to create boards. They’re analogous to the
ubiquitous .stl file format that mCAD programs export for
use in CNC milling, or the slicer program for a 3D printer.
The pattern and component editors allow you to create
the pad spacing and shape. You can use the component’s
datasheet in the event that the part isn’t in a particular
program’s parts library.
I personally use an eCAD program called Dip Trace that
was recommended to me. (I used it to create the
screenshots in this article.) This article won’t be going into
how to use programs or best design practices, so make sure
May 2014 35
Figure 1. Top and bottom
of a surface-mount
three-axis gyroscope.
Printed Circuit Boards
Coming 5/9/14 to the Nuts & Volts Webstore:
“Make Your Own PCBs with EAGLE”
www.nutsvolts.com
Check the video at
www.nutsvolts.com
and see how the
professionals at
Parallax apply
solder paste, place
components with
"pick-n-place,"
reflow the solder in
their massive oven,
and solder TH
components with a
"solder volcano."