Know Your Limits

Your own experience and access to tools play an important role in your design process.

Through-Hole vs Surface-Mount

Surface-mount, components are smaller than their through-hole counterparts. They can be tricky to solder, but not impossible for a beginner. See Prototype & Manufacture towards end of this book for some tips.

If you want to keep prototyping easy, or supply your design as a kit, then go for through-hole. If you want a compact, professional-looking board then surface-mount is the way forwards. Prepare yourself for some tricky processes if you choose SMD!

Bear in mind that not every part is available in both through-hole and surface-mount. Designs will often mix both types.

Size & Complexity

The bigger it is, the more it costs. The same goes for complexity. If you've got an elaborate idea, set it aside for now. Keep your first board clean and simple. Hone your skills, gain some confidence and then tackle something bigger.

The freeware version of Eagle limits your board layout to 100x80mm, which is big enough for most addon projects.

It will also limit your design to just two signal layers. This might spell disaster if you've got your heart set on a component that needs more. For now, simple is good.

Large PCBs, and ones with 4 layers or more, will cost considerably more than a simple 1 or 2 layer, small board. Keeping your design simple keeps costs low.

Cost & Funding

Until you start buying in bulks, component prices can be steep. Cost will play a big part in which components you choose, and how quick you move.

Ordering prototypes can cost you anything from £10 upwards. The price depends upon the quantity you want, how fast you want them and how good they are.

Every time you make a board revision, or a mistake, you'll need a new set of prototypes. Bear this in mind! Mistakes cost time and money.