Food for thought:
- The Ultra is a huge chip. There's no way a phone, watch, tablet, nor vision device could ever fit that fist-sized chip.
No way a Mini or MacBook or iPad Pro are going to fit it either. Mentioning the phone is just misdirection. The plain Mn , Pro , and Max won't fit that either.
- Die shrinks are increasingly ineffective for some SoC components
- TSMC is investing 2.9B in 'chip packaging plant' (for 2027)
I think that is mainly CoWoS-LSI packaging. Namely ....
" ...
For advanced packaging, C.C. Wei noted that, especially TSMC's chip on wafer on substrate (CoWoS), capacity is "very tight."
"But we are increasing our capacity as quickly as possible. And we expect these tightening will be released in next year, probably towards the end of next year, C.C. Wei had
said during the Q2 call. ..."
Taiwan Semiconductor Manufacturing (TSM) plans to invest ~T$90B ($2.87B) in an advanced packaging facility in Taiwan as AI demand heats up. Read more here
seekingalpha.com
These are ginormous MI300 , Intel Data center Max GPU (Ponte Vechicoo ) , Nvidia Grace like chips TSMC is chasing aftrer. All substantively larger than the Ultra.
If the big AI training chip trend keeps up, that is mainly where TSMC's packaging money is going. Apple isn't using that tech for the Ultra (so far) . That is the other issue. Whether Apple just is going to try to stay largely inside the reticle limit for the multiple die packaging efforts. TSMC will do more of that also in the future , but much of the revenue chasing they are doing now is toward much, much larger packages.
- Apple is at the forefront of low power draw/low heat designs
will loop back to this toward the end.... more chiplets isn't the lowest power draw.
- Apple is noticeably absent from any UCIe like standard
Apple is noticeably absent from a lot of standards. CXL . No AV!. No DisplayPort 2.0 . Abandoned OpenCL. No 3rd party GPU drivers. etc. etc. etc.
UCIe is mainly to enable logic dies from different companies to be coupled together. Apple is mainly interested in doing their own CPU , GPU , NPU, and eventually modem. They only really need an 'internal only' standard to couple those dies together. Apple's zero interesting in 3rd party GPU drivers is quite indicative of how many "other people's" dies they are hyper interested in coupling to.
It's obvious Apple and TSMC will start 'stacking' silicon.
Errrr, the A-series has been stacking dies for decades.
CoWoS-LSI has 'stacking' silicon but not particularly in the way you are suggesting.
Not chiplets, Not UltraFusion. The question is when. I'm sure they're experimenting with it now, but this new TSMC plant would be part of the process in 2027. That sounds like a good estimate for when Apple products are shipping with stacked SoCs.
Do something like decouple the memory controller logic from the main computational die? 'When' is a decent about of time.
Just stacking RAM or Cache isn't going to get Apple out of the constrained ditch they are in in trying to compete with the big dies spreading out over CoWoS variations that TSMC is spending billions to enable.
If you stack logic element dies then it is 'chiplets' that you are doing. So "Not chiplets" isn't it. UltraFusion is a relatively very low power hit for perf/watt but it is still a hit. As long as Apple is fanatically chasing maximum perf/watt , how deeply they go into the chiplet question is likely going to have problems. You have to 'give' on that front a bit ( not abandon, but just not quite so rigidly fanatical) to really seriously do a good chiplet strategy.
The Ultra is really a 'side job' that some monolithic dies are pressed into ... possibly grudgingly.
Similarly when Apple's Modem comes... not particularly likely that is going to be 'stacked on top' either. RAM is already stacked on top in most cases and if there is space in a phone for a discrete modem there is space for a bigger SoC package with both ( still could get a small decrease utilized. ) . Stacking vertically doesn't really get you more pins outs from the whole SoC. ( stack RAM which only 'talks' to the compute die doesn't have much 'outisde' pin out volume. A modems whole job is to talk to the outside/'off package' world. )