Hi,
I'm working in a design based on the BeagleBone where we basically made small modifications and manufactured the board. When we received it and started the tests we found out that the PMIC is not even providing the necessary voltages to let the processor boot. We are powering the board with the USB cable.
VLDO1 and VLD2 are not outputing any voltage so our guess it that the PMIC is at the OFF operation mode.
In our design, we connected a simple (with a button) circuit to the PB_IN to be able to start the board from a Li-Po battery but we believe that this is causing trouble (see the picture attached).
Our guess is that PB_IN (push button input) is kept low and for this reason the PMIC is in OFF operation mode all the time.
We base our conclusions in the assumption that VDD_3V3A (PB_IN is connected to VDD_3V3A) might be low because the PMIC is in OFF operation mode.
Does this make sense to anybody? Could anybode check our PMIC design and provide some feedback?
Any comments are welcome.
Thanks.