Ed Leckie wrote: > What about a multi-voltage supervisor for 1V2, 2V5 and 3V3 rails, > such as the STM6179 [1]
This is a nice chip, thanks ! Also availability in configurations suitable for us looks good. > rather than relying on an unregulated 5V from a wallwart. I'd also prefer to monitor the regulated side. However, the story is a bit more complicated, because M1 relies on the external supply for a number of things, including USB host Vbus and MIDI. So we already depend to a certain extent on the 5 V supply to be fairly high quality. One could make the case that, even if we have a problem on our 5 V rail, it would still be better if this didn't spread so easily to the rest of the system, i.e., amplified by the reset chip. On the other hand, the better you contain the problem, the less likely it is to get fixed ;-) > And perhaps should you use a 12V wallwart and and board 5V > switching (pre-) regulator? Oh, that's what I'd love to have. I find the whole "use a precision power supply and save an on-board regulator" concept very unappealing, particularly considering that M1 is likely to be used in harsh conditions. However, there is concern about making too many changes to a system that does basically work. A good change but with a rushed execution could easily create a lot of new problems. So I think it may take a while before we get sturdier on-board regulation. I think having a better reset chip is something worth looking into, though. That should be a fairly unintrusive change, the sourcing risk seems low, and we now have a very good idea of what we want from the reset circuit. Thanks, - Werner _______________________________________________ http://lists.milkymist.org/listinfo.cgi/devel-milkymist.org IRC: #milkymist@Freenode
