Tips/Tutorial on Single Sided Boards v Two Sided

[aziltz]

Hey Brian,  I've gotten pretty good at designing single sided boards, and I'd like to get into fabb'd boards a bit.

Do you have any comments or tips for making the switch from etched single sided board design to two sided fabb'd design?

[madbean]

Sure!

When designing a double sided board, set your bottom layer to be the ground plane. Start laying out your components as you would for a single sided board, but route all the traces on the top layer. As you move along, you will get trapped into an area where you need to route something on the bottom layer. This is fine.

Once you get pretty close to finishing the routing, start switching as much of the top layer to the bottom as you can, except for the 9v supply. In some areas you may run into too many bottom traces crowding an area which leads to a component disconnecting from the ground plane. In this case, experiment with switching top and bottom layers until you get as much of it on the bottom as possible.

If you follow these methods, you will end up with a layout where you get most everything routed on the bottom layer (good) with the power routed on the top (good) and a minimum number of traces on the top.

Best practice is to have all the top layer traces go one direction and the bottom ones go perpendicular to the top. Don't worry too much about that, though. Don't be afraid to use vias, but don't over-use them either. If you've done a good job routing, one or two vias will be all you need.

[aziltz]

thanks 'bean.  I may have other questions or confusions in the near future.