Looks great!
Don’t you want to use plated mounting holes to protect the masking? I have the library that I can email you if you need it. It’s likely you already have it though. I don’t know the name of the library that has the planted mounting holes but I can find out tonight if you want.
I looked at the board. It looks like you used 0.15" holes spaced 0.20" in from each end. It should be 0.125" holes spaced 0.15" in from each end. The rest looks cool though. 
Scud,
I have a template board that you could use that has the plated mounting holes in the right locations. I can email that as well if you want.
looks neat.
it doesn’t appear the enable input of the right hand regulator is connected.
probably should move the left hand input capacitor next to the via feeding power to the top left side regualtor to minimize ESR contributed by the trace.
the ground feeding input side of of the regulators is very different between them. the input power bus creates a major break in the bottom side ground plane. you could consider pushing the power input connector away from the edge of the PCB so you can route the power bus up near the edge and come down to each regulator in 3 heavy feeds, each decoupled at their big via by their respective low-esr capacitor.
certainly comming along though. what current is each circuit designed for again?
:mrgreen:
Scud,
Here is a pic of the Speak Jet/sensor board that I had made a while back. Its using the plated mounting holes and works perfect stacking with the SSC-32 or the ABB.
Hi guys,
Sorry, different time zone so another update 'll have to wait till tomorrow 
I forgot the synch part though, I kinda whipped up the update too fast, EddieB thanks I’ll try routing it that way, not happy with it, it’d never stand up to any decent amount of use with the currents we’re talking about in the design as it is right now… I think it’d be best if i can get the power lines on dual sides with vias running all through the traces to maximize current flow, but i’m not sure if vias have adverse effects such as skinning, maybe you have an idea on the subject?
SN96, if you could mail me the template with the drill holes that’d be sweet, I’ve been struggling with the d$mn holes for 30 minutes and they’re still not the way they should be
Ps: The components are rated at 5A continuous each, still not that much but it’s allready quite a daunting task 
Hi guys, new update…
SN96 supplied me with his template, unfortunately I couldn’t open it since my version of Eagle is too old…
Anyway i messed around with the holes somewhat and I think they should be okay now.
Implemented a synch clock too, but based it on a simple opamp to try and cut costs, the tinylogic devices seemed a bit pricy to my taste.
Rerouted the main power lines in three separate paths to divide the current path, and added more caps to conform with the high current pulses these things tend to pull.
Anyway, shoot yer comments this way.
Schematic
Bottom
Top
Full layout
PS: SN96, thanks alot for all the trouble, it’s really a shame it didn’t work out, but lemme know if I can ever do you a favor 
/edit: don’t mind the silkscreen yet, haven’t had time to manage that yet. Component values for the osc. circuit aren’t mentioned yet either, but the zener should be something like a 4.8v thingie
So has anyone actually built a working prototype of the muliplexing board?
er, I don’t think enough time has gone by to build prototypes yet. scud might have the parts and stuff accumulated by now though.
The switchers should arrive some time this week. Most other components I have at home, low ESR caps I can get at work.
The PCB’s would take about 10 days to get though, but I’m gonna wait for some more comments to make an order since I wouldn’t wanna miss anything.
These things aren’t like an 7805 circuit you’d build on a piece of perfboard
actually if you have the perfboard with the plated holes it isn’t “too” bad a job to prototype this kind of stuff but it’s not usually much fun to do either. I’ve used solder braid on these types of protoboards to make power busses before but it’s really ugly. If you have the time to wait batchpcb is a highly economical way to make prototype PC boards (if you also have the layout software and patience to use it.)
Back in the day (that makes me sound old doesn’t it) I used perfboard a lot, but since i discovered it’s not that hard to make your own pcb’s I’ve never looked back Not easy to make double layer boards though, let alone through-hole ones. I could always make some kind of a prototype, but I’m a bit cut for time these days to make one on perfboard.
When I get the samples I’ll make a prototype for a single switcher though, I allready have a print layout for it, and use the equipment at the lab at work to make some measurements.
EddieB thanks for the link, but thing is I’m from Belgium, so it’s faster and cheaper for me to use a local PCB pool
Sorry about that scud. I wish the template worked for you. I could try to create another one with an older version if you want to try again.
If you don’t want to mess with that, here is how I made the template:
change grid spacing to 0.1
delete the boards dimension border
select wire rout tool and chage layer type to “dimension” and make sure the 90deg routing is selected.
set wire width to zero
starting at the origin, draw a box, it does not have to be the right dimension.
click top line of box in the middle and resize it to 2.3"
click right middle line of box (board dimension) and drag it to 3"
8.) change grid spacing to .01 and move pads to the corners of the board. The holes centerlines should match the boards dimensions so that the mount pads center hole is perfectly centerd on the board corner.
To find the right size pad you need to make sure the “Holes” library is enabled and search for “pad” select the one caled Mount-pad-round2.8 you will need to add 4 of these in the schematic before you start.
If you have any questions let me know! 
wala! your done!
Mount-pad-round2.8 => I thought it was 3.2? 0.125" * 25.4mm = 3.175mm?
Where am i miscalculating 
Thanks for the walkthrough SN96!
Switchers arrived today, if possible i’ll etch a small prototype tonight.
Hey ScuD have you had any chance to work on this project at all?
Haven’t had a chance to yet, with the holidays and my girlfriend forcing me to take her to the coast ( 
) haven’t had the chance to get much work done.
PCB pools weren’t taking any orders anyway, but i’m gonna start looking for components and adapt the board (cap sizes are a bit too small i think, inductor’s right though), then order some.
It’s taking a bit longer than expected, sorry for that, but I promise I’ll get a working prototype soon!
heh, np. I, uh, have another PCB I had made recently that seems like it would pair nicely with these circuits so let us know how they work out when you have a chance.
forcing you to go to the coast 
EddieB; you got me curious, what is it what is it???
Oh and uhm…
Nice picture. You using a cnc mill to make pcb boards? “it” is a smart battery controller. I thought it might be interesting to directly put a high current regulator on the same PCB so anything from a 2S to 4S stack could be used and you would get the nice regulated output. still a lot of firmware to write though so… just thinking it forward a bit.
