finished PCB for synthesizer module, tips on layout?

[willbanks]

I know how to layout components but what I don't know are good practices to do when laying out components. I observed some boards and noticed a lot of synth boards have resistors next to eachother, traces going under an IC and not between pins, capacitors near power supply, etc.

If it isn't too much to ask for, tips on how I should change the layout of this board, if I did a big no no for design, etc.

Some info on the board:
This is an AD (Attack, Decay) generator. It produces a signal that has a variable rise time and fall time.

[endevor100]

Overall pretty decent. It's usually best to avoid acute angles like what you have to the right of R11. Especially for an audio application I would use a ground plane. It'll reduce signal noise and can make layout easier as you don't have to route the ground net as much.

[T3sl4co1l]

Yeah, rows are fun.  Pretty much the whole right side could be a single row of axial components.  Doesn't look like that would be difficult to route.

There's no ground plane, so expect it to be susceptible to ambient noise.

Why THT?  SMT is at least as easy, plus the board sits flat while you're working on it, and no cutting off leads required.

Tim

[willbanks]

isnt SMT much more difficult to solder? thats why its through hole, and i dont plan on a mass manufacture.

[T3sl4co1l]

Meh, 1206s aren't much smaller than 1/4W resistors already, and I've never met anyone who had a problem tacking them down.

Personally, I go with 0805 and 0603.  Below 0603, it gets much too tedious to do by hand, plus you'll definitely need magnification to inspect it (and if your eyes aren't so great, you'll need magnification while working, too).

Even when I'm using THT parts, I tend to surface mount them (dead-bug or Manhattan style construction).  It's so much easier than drilling holes in a one-off proto, or wiring up perfboard, constantly flipping it around to make sure you're connecting things right.  Everything is on top and in view.

If you don't feel that buying SMT parts is a good idea (maybe you're playing with THT parts on the breadboard, so you've already got stock of those), that's fair, too.

Tim

[Agent86]

Quote from: willbanks on Yesterday at 07:49:03 PM

isnt SMT much more difficult to solder? thats why its through hole, and i dont plan on a mass manufacture.

I was afraid of SMT before I tried it.  Now I don't want to go back!  Get yourself some flux and a set of tweezers and you'll find that SMT is *so* much faster than THT...

Check out this video: http://store.curiousinventor.com/guides/Surface_Mount_Soldering/101