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VonSzarvas wrote: »
Thanks, that helps diagnose.
Sounds like the left side usb power switch has half-blown, or the diode mod next to it needs some rework.
Either way they'll need a lab fix. If thats something you'd want to do, I could share instructions. Otherwise, best to contact Parallax support and see about returning it for diagnosis. I'll send a headsup to the engineer that'll handle it.
ozpropdev wrote: »
My P2_ES board appears to be suffering the same issue.
Trying to power the board from the P2-USB socket drags 5V down to 0.5V.
Board works fine from PC-USB but needs boosting as 5V is loaded down to 4.7V
cgracey wrote: »
Ozpropdev, do you know what is drawing such excessive current?
Tubular wrote: »
OzProp brought his board over
1. His board is still working fine when in normal "PC USB" (via ftdi) supply mode
2. When AUX power is added, the 5v as measured on header pin drops to around 72mV
3. FT_PROG shows same for his and mine, specifically PWREN# on C2 and C3 of FTDI
4. My anode reads 10040 ohms to ground, his 9560 ohms
5. Just powering from AUX side only results in 0V on the 5v header, rather than 72mV
6. We noticed, when powering from PC USB (ftdi chip side), the 5v header reads 72mV until enumeration takes place, at which time it jumps to 4.97v
VonSzarvas wrote: »
Next batch of P2 chips are due in May. There will be an Eval board available pretty soon after those chips arrive. Look out for announcements here early May.
rogloh wrote: »
How robust is the VIO supply on the P2-EVAL boards...?
I briefly touched an earthing post to V3239 for a split second and now my P2-EVAL board appears dead. Would the power regulator chosen for this not be short circuit protected? This was the latest type of revB EVAL board, not the original rev A design.
Update: board is back to life (after leaving it unplugged and to settle for a while, perhaps a polyfuse has saved it?).