BCM die size and picture

[hojnikb]

Is there any data of Rpis SoC die size ?
and possible a die picture like this

[jdb]

We have a wafer of 2835s in the office (belongs to Gordon).

The die is actually quite boring. The chip uses an overall top metal grid layer to distribute VDD and VSS across the chip in a low-impedance manner - this means that all you can really see is a flat grey grid across much of the chip.

[hojnikb]

Well, thats too bad. I was just wondering how big is Videocore4 compare to other modules on the chip. My guess is, that it must occupy quiete a big chuck of die, together with 256K L2..

edit:
Silly me, there is apperently only 128k L2 cache

[jamesh]

Well, thats too bad. I was just wondering how big is Videocore4 compare to other modules on the chip. My guess is, that it must occupy quiete a big chuck of die, together with 256K L2..

Yes, the VC4 is pretty big - when you consider its capabilities that's not surprising - but how big we are not allowed to say.

[hojnikb]

Yeah, i figured it has to be big, since it packs quite some heat
As for the exact number, i guess i understand why u cant give any specifics.. Videocore itself is quite a secret.

One more question though (hopefully it can be aswered without violation ndas):
Since broadcom is a fabless company, who is making the actual Pis chips (and are they packaging them aswell), also on what process node is it made.. ?

[jamesh]

I can say that the bcm2835 is 40nm, and it was first manufactured 4 years ago, so it's pretty old by current standards, hence the large process. Not sure what else I can say though.

Actually, considering how much it does, it's heat output is pretty low (no heatsink required...) - certainly market leading (at the time), and still very good now. It's one of the main selling points, very low power (and hence heat) for the performance.

[hojnikb]

I was kidding about the heat (i still think putting heatsinks or even fans on it is stupid); what i meat to say was, that considering how little power this thing uses and how small it is, it's defenetly powerful (gpu part atleast).

Thx for all the answers