Hi, I think that when you go below 6V something maybe starts to oscillate and= thus causes all the problems. Make sure you have at least 2.2 uF cap on the regulator input, as stated in= the data sheet otherwise the regulator may be unstable. *********** REPLY SEPARATOR *********** On 25/04/2003 at 17:11 stanton54 wrote: >I don't think that's the problem since it works fine as long as the >battery stays above ~ 6 V. I can speed up and slow down the motor and >turn it on and off and everything works fine. There is a diode going >backwards across the motor and 3 capacitors, plus a 10 uF cap right >next to the regulator. I also tried unplugging the motor as soon as it >shut off but the regulator still started getting hot. > >There is another regulator on the board, an LM2940, which interestingly >seems to be OK. I don't think anything hooked up to the 2986 is causing >trouble - the AVR stays cool and the R/C receiver isn't bothering it. > >I will draw a schematic as soon as I finish downloading Eagle. > >Bob Blick wrote: >> >> Is it possible the circuit is turning the motor on and off repeatedly? >> That could generate all sorts of mayhem, especially if you have no >> provision made for catching released energy from the motor. At the very >> least you should probably have a catch diode across the motor. Also you >> may need some bulk capacitance across the battery voltage. >> >> More description of the circuit or a snip of the schematic would help >> further diagnosis. >> >> Cheerful regards, >> >> Bob >> >> -- >> http://www.piclist.com#nomail Going offline? Don't AutoReply us! >> email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > >-- >http://www.piclist.com#nomail Going offline? Don't AutoReply us! >email listserv@mitvma.mit.edu with SET PICList DIGEST in the body ~~~~~~~~~~~~~~oOo~~~~~~~~~~~~~~~ Ofer Saferman, M.Sc. Senior Design Engineer Paragon Communications 6 Pal-Yam Haifa, 33095 Israel Phone: +972-4-8642775 Fax.: +972-4-8642737 e-mail: ofer@paragoncommtech.com -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu