Hi;
It’s hard to tell without looking at the ULN data sheet, but the ULN may have drawn too much current from the port. You may have to use a buffer and/or a level shifter to drive the ULN. Bill "No one could make a greater mistake than he who did nothing because he could do only a little." "All that is necessary for the triumph of evil is that good men do nothing" Edmond Burke (1729 - 1797) http://www.packtpub.com/building-a-home-security-system-with-beaglebone/book From: [email protected] [mailto:[email protected]] On Behalf Of Carol Hsin Sent: Monday, July 21, 2014 8:10 PM To: [email protected] Subject: [beagleboard] why BBB died? datasheets/multimeter seem to indicate it shouldn't have I'm using a ULN2003AN to actuate a 24V/3W solenoid valve. After I set pin P8_11 to HIGH, the solenoid clicked and its power led turned on, then the BBB died. I tried turning the BBB power on again, but all that happens is that the power led flashes briefly. I had checked everything w a multimeter before hooking up the system. The solenoid is 177 ohms; hooked to 24V, it reads 0.151A -- which is under ULN2003AN's .5A max and matches its datasheet (AVS-5322-24D on http://www.automationdirect.com/static/specs/nitradirectionsolenoidavs5.pdf). There shouldn't be a problem. And the ULN2003AN isn't broken. The BBB and transistor worked fine for a more expensive solenoid valve (VUVB-L: http://www.festo.com/net/SupportPortal/Files/17267/Ventile_en.pdf). I've tested it with that valve and the multimeter read 374 ohms; hooked to 24V, it reads 0.062A. I don't understand why the BBB died. It shouldn't have because I was careful about checking the datasheets and then w the multimeter. Would someone please tell me what went wrong? I can't see any mistakes. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout. _____ No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4716 / Virus Database: 3986/7863 - Release Date: 07/16/14 -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
