open-source-silicon.dev

So how do you recognize pin 1 on the chip ?

Ok, well I guess the only way is to look at the traces on the RDL and match that to the bonding plan.

That's a good question and I have the same thought :thinking_face:

The way I did it is that there is a track that "splits" in two and pretty much surround one of the ball. It's pretty easy to spot and that's on the side opposite to pin A1, so I put that aways from the pin1 marker on the pcb when soldering.

When I did the RDL layout, I assumed that there would be some kind of marking on the top of the chip.  Otherwise, I would have put some kind of indicator for pin A1 on the bottom in RDL metal.