Hi !
Update on the PIC18F14K50:
Today I refined the battery charger detection, I can now determine with kind of power supply is connected to the PIC.
So in this article I am going into a bit more detail about the power supplies
The first kind is a Phihong PSB05R-050Q, it has both D+ and D- pins pulled to 3.3V by a voltage divider.
You know: Don't turn it on, take it apart. In this case (sonic welding) I needed a handsaw.
The second one is the ITE AC024-53100:
This one has 2 USB ports, one "Smart out" with that little SOT-23 chip and another one with D+ and - shorted,
you can see that above the little SOT-23 chip.
The third kind which I don't have a photo of is just nothing connected to the USB D+ and D- at all.
Here is the reverse engineered output circuit of the Phihong compared to a simple shorted one:
In The Phihong its like a 3K Ohms pull up to 3.3V. That's what the impedance of the voltage dividers is.
There is more to come... stay tuned!
Cheers,
Chipguy