Re:Photographing a Raspberry Pi 2 with Xenon flash makes it ...
by amelius on Monday November 08, 2021 @11:27AM
(#29150946)
The reason could be the same as given in the other RPi post today (about the Pi Zero 2W):
> The black rectangle is a "bare-die soldered bumped package"... what that means is the silicon die has no black epoxy covering. A metal layer is deposited on the die and then solder bumps attached which allow the part to be soldered to a PCB. The reason for this, is as expected, cost. No package (epoxy, substrate)... no cost. One sees this more-and more with electronic assemblies.
> The only downside is that external light can actually affect the chip operation (light hitting the die releases electrons at PN junctions creating errors in circuit operation ) .. .however here the Faraday metal shield helps prevent this.
> The black rectangle is a "bare-die soldered bumped package"... what that means is the silicon die has no black epoxy covering. A metal layer is deposited on the die and then solder bumps attached which allow the part to be soldered to a PCB. The reason for this, is as expected, cost. No package (epoxy, substrate)... no cost. One sees this more-and more with electronic assemblies.
> The only downside is that external light can actually affect the chip operation (light hitting the die releases electrons at PN junctions creating errors in circuit operation ) .. .however here the Faraday metal shield helps prevent this.
http://electronupdate.blogspot.com/2021/11/raspberry-pi-zero...