I’m trying to design a product with the BC127 and I’m using the Sparkfun breakout board to prototype some things before I make the PCB. I’ve been having some issues with not being able to detect when the charger is plugged in. I also have a CSR dev board and this works fine. I noticed on the Sparkfun schematic that they have VCHG connected to VIN. From the Sierra documentation it looks like VCHG should be connected to VBUS. (VIN is either VBAT or VBUS - the voltage going into the 3.3V regulator.)
This seems like a mistake, since VCHG will have a high voltage even when the charger isn’t connected. Anyone else have any experience with this?