iPhone Air How does the Air have such great thermal management with a titanium frame when the Pro couldn’t pull it off?

[Brettka7]

I’ve had my iPhone Air since launch day after swapping over from a 16 Pro Max.

The 16PM was easily the warmest phone I’ve ever had. It made my hands clam up at times and my CarPlay was non-functional if I was wireless charging, playing music, and navigation all at once. It would freeze up until I removed it from the charger.

The moment I got the iPhone Air, my heat management problems disappeared. The battery section is never hot and the plateau is only rarely warm.

It makes me wonder the technical aspects - why couldn’t Apple package the Pro phone similarly to the Air, keep the titanium frame, and supplement it with the new cooling system? Is there a fundamental difference other than the thinness? I’ve even seen 17 Pro owners stating their phones are still getting pretty warm, just not as warm as the 15/16 Pros.

 

[turbineseaplane]

Perhaps the Air performance gets throttled to keep it within a certain thermal envelope?

(like Air Macbooks)

 

[JPack]

In short, it's because the Air doesn't have a good cooling system. So you're less likely to feel heat because it's not being dissipated, which in turn means lower performance.

If you look at teardowns, the Air's chip barely makes contact with the glass plateau and glass itself is a heat insulator.



On the other hand, the 16 Pro/Max chip makes full contact with the metal mid-frame.



This is like MacBook Neo, where the chip is not covered by a metal heat spreader. So of course there isn't much heat felt because it's not being dissipated effectively. MacBook Air improves this with a heat spreader and MacBook Pro has a finned heatsink.

 

[Brettka7]

In short, it's because the Air doesn't have a good cooling system. So you're less likely to feel heat because it's not being dissipated, which in turn means lower performance.

If you look at teardowns, the Air's chip barely makes contact with the glass plateau and glass itself is a heat insulator.

View attachment 2644295

On the other hand, the 16 Pro/Max chip makes full contact with the metal mid-frame.

View attachment 2644296

This is like MacBook Neo, where the chip is not covered by a metal heat spreader. So of course there isn't much heat felt because it's not being dissipated effectively. MacBook Air improves this with a heat spreader and MacBook Pro has a finned heatsink.

This is super interesting! I haven’t noticed a single issue with performance on my Air and it in fact solved all my performance complaints from my 16PM, but the teardown doesn’t lie.

I also have to wonder if these new chips just run cooler considering my wireless charging and direct-sun overheating issues no longer exist.

 

[JPack]

This is super interesting! I haven’t noticed a single issue with performance on my Air and it in fact solved all my performance complaints from my 16PM, but the teardown doesn’t lie.

I also have to wonder if these new chips just run cooler considering my wireless charging and direct-sun overheating issues no longer exist.

Even with throttled performance, the A19 Pro outperforms the A17 Pro.

If we look at throttled A19 Pro (Air) vs. A19 Pro (Pro/Max) the sustained difference is like 20% and 2W.

The Pro/Max chassis tries to extract as much performance as possible from the chip at the expense of heat and power.

 

[SevenTheGamingKitty]

In short, it's because the Air doesn't have a good cooling system. So you're less likely to feel heat because it's not being dissipated, which in turn means lower performance.

If you look at teardowns, the Air's chip barely makes contact with the glass plateau and glass itself is a heat insulator.

This is like MacBook Neo, where the chip is not covered by a metal heat spreader. So of course there isn't much heat felt because it's not being dissipated effectively. MacBook Air improves this with a heat spreader and MacBook Pro has a finned heatsink.

wait... so the iPhone Air feels better at thermal management because it's *worse* at thermal management...?

 

[JPack]

wait... so the iPhone Air feels better at thermal management because it's *worse* at thermal management...?

No, you’re confusing surface temperature with thermal management.

Thermal management includes the movement and removal of heat for device reliability and performance.

If we covered the chip with a piece of styrofoam and you couldn’t feel the heat, nobody would call that good thermal management.

 

[conmee]

Air is also down one GPU core as well... one less coal in the oven furnace.

 

[James6s]

I have an Air and there are times when the plateau gets warm if you happen to touch it during some processor intensive work.

I think because everything is in the plateau up top you don’t tend to feel it if it’s getting warm because of where you naturally hold it.

Never had any throttling issues or slow downs.

 

[Gorlammi]

Even with throttled performance, the A19 Pro outperforms the A17 Pro.

If we look at throttled A19 Pro (Air) vs. A19 Pro (Pro/Max) the sustained difference is like 20% and 2W.

The Pro/Max chassis tries to extract as much performance as possible from the chip at the expense of heat and power.

This is exactly correct. The A19 is simply outperforming the A17 and OP isn't pushing it to its limits.

 

[maerz001]

Interestingly this week another Air user:
„If I take my phone out of my pocket to use it, outside in direct sunlight, this phone gets massively hot very quickly, in only a few minutes.“

After having the Air since October I finally found a negative thing about it

My 15 Pro overheats a lot. Even with the AC running in my car, it routinely stops charging (via cable, not MagSafe) at 80% because of heat. Would also recommend Low Power Mode to anyone looking to reduce power/heat.

forums.macrumors.com

 

[JPack]

Interestingly this week another Air user:
„If I take my phone out of my pocket to use it, outside in direct sunlight, this phone gets massively hot very quickly, in only a few minutes.“

After having the Air since October I finally found a negative thing about it

My 15 Pro overheats a lot. Even with the AC running in my car, it routinely stops charging (via cable, not MagSafe) at 80% because of heat. Would also recommend Low Power Mode to anyone looking to reduce power/heat.

forums.macrumors.com

What a shocker. Direct sunlight heats up the iPhone?

What’s next? “If I submerge my MacBook under water, it gets waterlogged real fast!”

 

[shady16]

Yeah the air does get warm it’s just with all the phone in the plateau it doesn’t get hot where you hold your phone. I have both the air and 17PM and actually you can notice the heat more in the 17PM but that’s because of the vapor chamber and aluminum spreading the heat over the chassis where as the air the heat is localized to the top. I work outside and my air has dimmed before but unless I touched the plateau I wouldn’t notice the heat

 

[Earwolf]

Yet again, you're holding it wrong