On 8/29/08, Joerg Reisenweber <[EMAIL PROTECTED]> wrote: > Nope, Tranzorb won't help here because the energy this component had to absorb > is too high, so it would burn out. Transzorbs are for ESD surge suppression > only. Yes, but the trick is that they burn to a short circuit. You still need a fuse element in front that burns garanteed open ( fuse, resistor ) Design target is to aim for a reasonable repair and avoid a fullbrick.
> However meanwhile main rant here seems to be about additional cost for a > ~$0.05 diode to clamp reverse voltage and trip the polyfuse we have in new > GTA03 design. Obviously there is a notion customer wouldn't like to pay this > price for increased ruggedness of USB-power input. Also there have been > objections about the safety of such a design, not taking in account that it > can not be less safe than what we had originally. > same applies here if you use the unsymmetric variety. Overvoltage and reverse voltage draw current through the TransZorp long enough to have the fuse blow. Save! A freerunner is more of a cherished posession than forex a Motorola F3 ;-) uwe _______________________________________________ hardware mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/hardware
