On 9/8/05, Jack Carroll <[EMAIL PROTECTED]> wrote: > On Thu, Sep 08, 2005 at 11:52:51AM -0400, Timothy Miller wrote: > > > > (1) We need a test power supply circuit built and tested. > > > > We have a schematic for the power supply circuit designed. We need to > > build one on copper clad or something like that and test. Primarily, > > we need to see how much noise is in the output. If someone could > > build that for us, we can tell you how to measure it, or you can ship > > it to us for testing. > > I've got a lot on my plate right now, and no scope at home, but I > could help a little with this one. If you shoot me the schematic PDF, parts > list, and input and output electrical specs, I can do a pretty realistic > calculation of the output ripple and trash. If you're using parts I don't > have data sheets for, I might need to ask for copies of those too, if > they're not easily available from the web. I can also suggest PCB design > instructions to make sure the board as laid out achieves the predicted > ripple level. I've done that several times in the last couple of years. > What's the board layer arrangement, GND and Vcc in the middle, and > two signal layers each top and bottom? > > Another thing I could whack out pretty quick is a standard set of > PCB fab drawing notes. I think I remember most of what I wrote at the last > company.
Ok, since I don't grok this stuff so well, I'm afriad I won't make a good middle-man, but Howard seems to prefer a physical circuit, because there are issues with how the layout can affect things. What he would do is us copper-clad and build something very much like the circuit for the final PCB and then test it on a scope. But simulating it in SPICE, if you can accurately model the PCB traces, might work just as well. In any event, if your concern is cost, just send me a bill for the parts and other materials you need. _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
