Pogo pins power clarification - reading schematics
03-25-2021, 09:23 PM
Haha no reason to be sorry, no obligation @scholbert. I liked your idea of the condensed picture, and I hope it helps others to find the right parts to look at to understand things more easily!
I don't think I have many questions left, but at least one thing is still on my mind: What happened with @GregH's phone here?
My guess: There is no charging because VBUS_CTRL is high, which means the PMIC ignores its DCIN input. But, there are now two power sources (5 V regulators) connected together at DCIN like this?
Should that be avoided? Similar to how we should avoid connecting 5 V to DCIN while a charger is connected to the USB C port?
@GregH's phone didn't catch on fire. Is that "luck", or is there something about the design that makes this ok or "safe"?
(Note: Now I understand that this doesn't create a "loop" inside the phone, because the PMIC ignores DCIN while the LPW5206 is enabled)
I don't think I have many questions left, but at least one thing is still on my mind: What happened with @GregH's phone here?
(03-01-2021, 12:24 AM)GregH Wrote: * I then attached the USB device without supplying power to DCIN. USB device worked fine. Good.
* I then supplied +5V to DCIN. Good new? No magic smoke! Bad news? No charging.
My guess: There is no charging because VBUS_CTRL is high, which means the PMIC ignores its DCIN input. But, there are now two power sources (5 V regulators) connected together at DCIN like this?
Code:
Battery -> PS -> LP6226 -> USB-5V -> LPW5206
\
--> DCIN -> USB C port -> USB device
/
External 5 V source -> pogo pin -----------Should that be avoided? Similar to how we should avoid connecting 5 V to DCIN while a charger is connected to the USB C port?
@GregH's phone didn't catch on fire. Is that "luck", or is there something about the design that makes this ok or "safe"?
(Note: Now I understand that this doesn't create a "loop" inside the phone, because the PMIC ignores DCIN while the LPW5206 is enabled)
