Hello: I'm using the OMAP 3503 and the TPS65950 on a Gumstix Overo Air module. The modules, and my baseboard, are working fine, stable, reliable. We have a TI MSP430 power controller that is powered on all the time, but controls +3.3V_Main to the Overo module.
Normally, everything works fine. But very rarely, on about 10% of our units, when +3.3V_Main is enabled, the PMIC does not enable core power to the OMAP, so the system does not boot.
VBAT to the Overo Air module (to the PMIC) is connected to the same +3.3V power that the MSP is powered by, and is on all the time. We are actually floating SYSEN and PWRON to the PMIC (is this ok?).
I can recover the system by killing VBAT on a lab bench, but this is unacceptable as an embedded system.
Can you please help brainstorm what might be going on here? I couldn't find any clues in the Gumstix forums, so I decided to check TI directly. Thanks very much.
