Quote from: Helium007 on January 21, 2020, 19:15:05Within the scope of running Spec, IIRC that test lasts for over an hour, so the figures quoted is close to stable numbers of a sustained load, there were efficiency numbers derived after all, and in another article there was a hot/cold comparison of efficiency, hot is the default numbers quoted at Anandtech and cold is the peak achievable before throttling, A13's cold was...I think >7W, hot is what you read from the link.
OK, my bad for forgetting "2 W from the SoC only" word.
It still doesnt make a big change of my point there. This actually can reach for 3W peak (for some time) in good thermal scenarios, like usual 25C ambient temperature and phone cooled to this temp.
Anyway if you look to Anandtech comparisons, you can still see that there is 20 up to 50% power gap in benchmark in peak/sustained load. So his is actually supporting my talks that phone "thermal solution" is really not designed for sustained load and is very under-dimensioned because of design and price. In laptops you will never see such drastical performance change.
And final thing - I have at work devkit with NXP IMX8 4x1,5 GHz 28nm SoC that can disspate 4W (here I can tell exact number beceause datasheet is not under NDA and states this). I applied custom heatsink about 15x15cm with fan guess what? I always get consistent benchmark numbers, no matter how long I run it. This wasnt same with factory heatsink it came with.
One thing that would be interesting to see thermal limits on these SoCs, because almost all have datasheets under NDA. I wonder how they set up thermal die limits. Because no one cares about long live of phone, they could set it very high to bump absolute raw power...
Quote from: Helium007 on January 20, 2020, 22:52:10"Typical smartphone can dissipate about 2 Watts of energy" is what you said, so I naturally assumed a total, only assuming that the SoC alone would be the component with the largest increase in power draw under load and if something notably throttles under load it would be the SoC itself.Quote from: S.Yu on January 20, 2020, 17:26:36Quote from: Solandri on January 19, 2020, 21:20:54No, instead it would make the 5W figure fairly accurate, for example Mate30P, NBC's numbers, 4500mAh, 3.65hrs load, that's about a sustained load of 4.56W. Only sustained load measures the heat dissipation between room temperature and the temperature allowed for the SoC.
With the 3000 mAh battery found in typical phones, @ 3.7 Volts, a power draw of 2 Watts would completely deplete it in 5.5 hours. 5 Watts would deplete it in 2.2 hours. 8 Watts would deplete it in 1.4 hours. So I'd say the 2 Watt figure is pretty accurate.
Well how do they measure that? Thats not SoC LOAD but total POWER input I guess. This is probably total power input and even if it would be total power dissipation (which you cannot measure easily), it would be dissipation of ALL components. For example RAM and PMIC chips are dissipating quite big amount of power. Only way how to get some sort of approximate SoC dissipation values could be cutting all SoC power lines and connecting them to bench supply...
So I am still standing with walues about 2 or 2,5W peak.
Sorry but my job is embedded electronics design and manufacturing, so I really would like to hear some reasonable infomation about this
Quote from: S.Yu on January 20, 2020, 17:26:36Quote from: Solandri on January 19, 2020, 21:20:54No, instead it would make the 5W figure fairly accurate, for example Mate30P, NBC's numbers, 4500mAh, 3.65hrs load, that's about a sustained load of 4.56W. Only sustained load measures the heat dissipation between room temperature and the temperature allowed for the SoC.
With the 3000 mAh battery found in typical phones, @ 3.7 Volts, a power draw of 2 Watts would completely deplete it in 5.5 hours. 5 Watts would deplete it in 2.2 hours. 8 Watts would deplete it in 1.4 hours. So I'd say the 2 Watt figure is pretty accurate.
Quote from: Hiktaka on January 19, 2020, 00:59:47
It's not that I'm going to argue against this type of article (it's useless),
but people dissing Geekbench as 'incomparable between iOS and Windows' 'only tests very specific scenarios' yada yada.. simply doesn't get it that Apple A series chips are really faster than x86.
Quote from: Helium007 on January 19, 2020, 22:57:16There's really no need to dive into the theoretics since phones are regularly tested for sustained load at NBC, and they're far higher than 2W. Also most phones these recent years have heat pipes, far more efficient than aluminum fins.Quote from: S.Yu on January 19, 2020, 17:03:29Quote from: Helium007 on January 19, 2020, 01:27:04Without going into any physics that sounds too low by experience, 5-8W is more like it, even by NBC's sustained load numbers alone. It also scales with the temperature difference.
Typical smartphone can dissipate about 2 Watts of energy
Well I wasnt pessimistic. You can check it here (one of few online heatsink calculators for free):
celsiainc.com/resources/calculators/heat-sink-size-calculator/
For 5W thermal dissipation, heatsink of aluminium at 25C with size 15x8x2mm with fins(!) it will be about 50% of required size/area. And I allowed 95C of max case temperature which is usual max for commercial parts.
Also important is that phones use their midframe as heatsink that actually is not a good heatsink material - typical AZ91D magnesium alloy has less than 50% thermal conductivity than tradition heatsink aluminium used in laptop coolers.
Phones do not have any airflow that makes any heatsinking the worst case scenario. Another thing is that x86 CPUs have direct thermal contact from silicon to heatsink so its more effective. Phones SoC have standart plastic epoxy cases, not optimized for heat sinking at all. This will cause the fact that even the chip actually can dissipate e.g. 5W, the transfer resistance of package will never allow it to dissipate (fast enough) for longer time than few miliseconds, because die will heat up over thermal limit.
All this combined will never allow to make any chip in mobile/tablet to compete their desktop counterparts. Maybe silicon in them yes, but not without doing special "desktop/ laptop" type package and absolutely different active heatsink solution.
Quote from: Solandri on January 19, 2020, 21:20:54No, instead it would make the 5W figure fairly accurate, for example Mate30P, NBC's numbers, 4500mAh, 3.65hrs load, that's about a sustained load of 4.56W. Only sustained load measures the heat dissipation between room temperature and the temperature allowed for the SoC.
With the 3000 mAh battery found in typical phones, @ 3.7 Volts, a power draw of 2 Watts would completely deplete it in 5.5 hours. 5 Watts would deplete it in 2.2 hours. 8 Watts would deplete it in 1.4 hours. So I'd say the 2 Watt figure is pretty accurate.
Quote from: LOL on January 19, 2020, 05:19:02It's not like apple just happens to make their chips at the time of year when tsmc is done with their new node and then Qualcomm uses it when they make their next chip. If anything Qualcomm would get priority over apple because their flagship chips sell more than apple's, not including all their other mid and low end chips that apple doesnt compete with.
We'll reach sub-1nm before the end of the decade. Can't wait! ;)
Combined with solid state batteries, I predict the battery life of phones and wearables will reach legendary 30-day standby times of Nokia 2G candybar phones of the early 2000s.
Apple (TSMC) is always one step ahead of whatever Qualcomm puts out, so for the Android phones, 5nm Snapdragons should be in 2021-22.
Quote from: S.Yu on January 19, 2020, 17:03:29Quote from: Helium007 on January 19, 2020, 01:27:04Without going into any physics that sounds too low by experience, 5-8W is more like it, even by NBC's sustained load numbers alone. It also scales with the temperature difference.
Typical smartphone can dissipate about 2 Watts of energy
Quote from: Helium007 on January 19, 2020, 01:27:04Without going into any physics that sounds too low by experience, 5-8W is more like it, even by NBC's sustained load numbers alone. It also scales with the temperature difference.
Typical smartphone can dissipate about 2 Watts of energy