open-source-silicon.dev

Trigger warning: soldering anxiety:
<https://www.youtube.com/watch?v=edERx4x5eY0>

that is just super-cringe ... on soooo many levels...

What I've seen done to solder such small wlcsp is to actually use a large tip iron with a solder blob, flux, and just heat the chip from the top with the soldering iron until the ball reflow on the pcb ...

there are merits to any approach that eventually "works" I guess .. but I am not a fan of methods that are not particularly reproducible/under some type of process control

I would liken such methods to the "it works on my machine" idea in software ... this is the "it works on my board"

<https://www.flickr.com/photos/37778900@N06/8157091493/>  0.5mm pitch bga (not csp but similar) It worked fine including 480Mbps USB.