Hi all, I've been working on a project in the past couple of days, while trying to teach myself to use Diptrace a bit better, and at the same time solving my problem of not having a truly pocketable headphone amp.
My design is a tiny, smd based Cmoy-style amp, which will be usable with the parts that I have available for cheap and not too much hassle (international shipping etc.). I've selected a buf-634 (to packaged) virtual ground. My first pcb design is as of yet untested since I'm waiting on my SMD parts to arrive, but it's simple enough that I'd think it'll work (perhaps with some bugs)
all resistors are 0812 size for ease of use.
This is my design, including the power supply. I haven't specified values yet since its still an early prototype, and I'm using a few shortcuts (eg, 2 sets of headers arranged for use as the potentiometer pads)
My amp is based on a tiny 20x30 mm board which I'm hoping will be possible for pretty much anyone to toner transfer and do at home. I've had success with as small as .3 mm traces, but this board will be all .4 or greater for the sake of making it a little less finnicky. It's going to be single sided, again for ease of making it, and that it constrains me to routing in a bit better
I'm sure any decent commercial board maker wouldn't have any trouble with it at all, but I'm aiming to make it workable as a home made product (preferably with very few or no jumpers.)
My first design is just the amp itself, since I have a power supply made with strip board to fit onto a 9v battery clip, and then wiring that to the seperate amp module. I've found it can be easier to fit into really small places if it can be separated out, though my final design will be for a single board, single battery solution.
If anyone wants to post some critique or anything (and make sure my design is entirely sound!) it'd be hugely appreciated. So far this project has been really interesting, and its definitely helping to develop my skills at pcb layout in CAD.
I'm going to etch my first prototype in the next day or 2, and will let you all know how it goes. I shall also be posting some follow up to this when I get the time (and enough material to justify a thread of it's own.)
Anyone who's looking for a really simple but pretty damn powerful design tool, that has a very reasonable learning curve, I'd suggest having a look at DipTrace. It has a free version, and personally I think it's a much better tool than eagle, KiCAD and all the other free tools I've tried on windows or linux. Eventually I'd like to learn Altium, but I figure, one step at a time.