I'm trying to identify a component on a GoPro Hero10's PCB.
It measures 1x1mm and appears to be a UDFN-4 package (or similar). It is grouped with one capacitor and doesn't have an obvious connection to a larger IC.
I have highlighted all relevant traces I could identify. The board is an HDI PCB with about 10 layers and blind/buried, plugged micro-vias, which makes things difficult.
The connector on the right is for the GoPro's front screen, the one right next to the long red trace is for the USB port.
The test point above the component in question appears to be connected to a via which would end here if it went straight through all layers (it most likely doesn't):
Here's an overview showing the PCB in its entirety from both sides:
Here's a close-up of the chip in question:
I'm not sure what kind of component this could be, which makes searching for it really difficult.
Does anyone have an idea what it is?
Best Answer
Thanks to some kind person on r/askelectronics, I can now provide an answer to my own question: It is a voltage monitor, which generates a reset signal when the supply voltage drops below 1.67V.
Part number: TPS3839G18DQN
I was (and kind of still am) confused by the wide VDD trace, given that the TPS3839 doesn't require any significant current but I looked through all datasheets I could find for TI-products with this package type/size and this was the only one with a "ZL" marking.
It's also most definitely a TI chip due to the marking style. Most other manufacturers use a dot as a pin 1 marking on this package but TI uses this little bracket. Although I could not find a picture that shows the TPS3839's top, other X2SON/DQN ICs from TI (in this case an LDO) look just like the one on the GoPro's PCB: