On Sun, Nov 6, 2016 at 7:26 PM, Bob Blick wrote: > If it's a lithium-ion or lithium-polyester, how about using a 1-cell > protector chip specifically designed for it, like the CS213? > I was kind of thinking that - though the battery supposedly already has one. He's sending me the bits and I'll do some testing - and I can prototype the solution otherwise. If not one of those, then the 10F PIC is looking a good solution (though as mentioned before I might go for an AtTiny10 simply due to better recent familiarity - I'm not sure I even have anything to programme a 10F). Is it possible to use VCC as a reference and measure the value of the internal voltage reference against that (maybe by sending the reference voltage out on a pin)? If not I'd surely need a voltage divider. I'm in the UK, but in any case these devices aren't going on sale - I'll check if there are any regs I need to meet, but I don't think there would be - will be used by a commercial company, but as part of kit they lease/loan out and any arrangement with me certainly wouldn't involve me selling to them. Thanks for all the help, Chris --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .