No battery Vsys issue is USB overcurrent?

Andy Green andy at
Mon Jun 30 19:43:32 CEST 2008

Hash: SHA1

Somebody in the thread at some point said:
| Andy Green wrote:
|> I really couldn't make a story for it, GSM power is controlled by
|> another FET switch U1705 that is enabled by a PMU GPIO, there is not
|> even a path to VBAT (GSM power rail) during all this.
| That's not the VB->U1705->VBAT->GSM path, but the
| VB->VB_GSM->U201.VBATT path. Has a nice 22uF bypass on it (C208).

I remember this now, there's no switch on it because when there was a
switch on it, sometimes it blew the current limit.  Leading to the logic
that enabled the RF power amp having switched power but not the RF power
Amp itself :-|

Unfortunately it's the same setup in GTA02 A3, if that's a valid clue.
Or maybe Graeme's A3 unique point is that it has a good backup battery?

Anyway the main battery + pin shows no signs of any dents or load and
sits there at about 0.4V itself before during and after the fun on Vsys.
~ I don't think this can be it.

- -Andy
Version: GnuPG v1.4.9 (GNU/Linux)
Comment: Using GnuPG with Fedora -


More information about the openmoko-kernel mailing list