[Lafleur]

We had a DS die on us, +5v led on, no VBATT led, no 6V led on.. (odd combination as VBATT is 12v and that's what drives the +5v and +6v switchers)

Opened up the unit and Q1, the reverse voltage FET was blown.. Well its was in many pieces... Removed it, the +6v switcher was again working and the VBATT led was back on... Ordered an new FET from Digikey and all is well...

Whats odd here is this unit was in our TEST robot, and the hardware configuration had not change in weeks, remove the bad unit, replaced it with a new unit and we were back in business... do not understand the root cause of the failure... it might just be a bad part!!

tom lafleur
mentor team 812
the Preuss school at UCSD