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Logical reasons why the iPad mini does not have Retina

ArchAndroid

ArchAndroid

macrumors regular
Original poster
Aug 26, 2012
101
9
London, England
Rather than get embroiled in the emotional reasoning why the Retina display was not included, I decided to take a look at it from a numerical and logical angle. I wanted to see how feasible it would be to fit in an iPad Mini so I cross examined the device with other Apple devices.

Die Size

Apple A5X: 163mm2 (45nm process) for iPad 3
Apple A5: 122mm2 (45nm process) for iPad 2, iPhone 4S

Apple A5X is 33% bigger than the A5 in order to power a tablet retina display.

Apple A5r2: 71mm2 (32nm process) for iPad 2,4, iPhone 4S

Apple A5r2 58.2% as big as Apple A5.

Apple A6: 97mm2 (32nm process) for iPhone 5

I assume that all of Apple’s allocation for chips at Samsung’s 32nm foundry are currently being used to make Apple A6 chips for the iPhone 5 and Apple A6X chips for the iPad 4 and that there is no extra capacity for iPad Mini.

Volume

*modeled as a cuboid shape as it is impossible to calculate the rounded edges of each iPad

iPad 3: 241.2mm x 185.7mm x 9.4mm = 421.033cm3 *

iPad Mini: 200mm x 134.7mm x 7.2mm = 193.968cm3 *

iPad mini has approximately 46% of the internal volume of an iPad 3.

Thermals

Anand Shimpi from AnandTech, on the iPad 3:
“The increase in power consumption of the new iPad also manifests in the form of increased heat production. A 163mm^2 SoC built on a 45nm LP process is a serious chip. Although it doesn't run hot enough to require active cooling, the SoC alone is responsible for a couple of watts of the iPad's TDP under heavy load. Combine that with a 45nm LTE modem and the heat put off by the more powerful backlight and you've got a recipe for a noticeably warmer device.
Does the new iPad get warmer than the previous one? Absolutely. I would even go as far as to say that it can get uncomfortably warm, but it never gets too hot to hold.”
Click to expand...

Imagine how hot the iPad Mini would become if you had to dissipate the heat from an enormous chip in a chassis which is less than half the size of its larger equivalent. It would be unbearably hot to touch and that wouldn’t augur well for the longevity of the device nor its components.

Battery Size

iPad 3: 42.5-watt hour
iPad Mini: 16.3-watt-hour

In order to power a Retina capable chip manufactured on the last generation Samsung 45nm process, the iPad Mini would require a battery approximately 2.5 times as big as the one it has. Additionally, this battery would have to fit in a volume of less than half that of the big iPad.

Weight

iPad 3 Retina: 652g (WiFi)
iPad Mini: 312g (WiFi)

iPad Mini weighs 47.85% as much as the iPad 3

Weight to volume ratio

iPad 3: 652 ÷ 421.033 = 1.54g/cm3 *
iPad Mini: 312 ÷ 193.968 = 1.61g/cm3 *

The iPad 3 and iPad mini have basically identical weight to volume ratio once you factor in the inaccuracy of my model for calculating the volume. The additional weight required to put in a battery 2.5 times as powerful would make the iPad mini noticeably more unwieldy than its predecessors.

Pixels Per Inch

iPad 2: 131.96
iPad 3: 263.92
iPad 4: 263.92

iPad Mini: 162.03
iPad Mini Retina: 324.05

iPhone 5: 326

This could actually pose a problem for Apple as their entry level unit would have much better pixel density than the flagship iPad, taking away a major unique selling point from the bigger tablet. The display would almost have parity with that of the iPhone 5, another Apple flagship device.

Future Models

When Apple moved from the Apple A5 to the A5r2 (45nm process to 32nm process), they were able to cut the die size by about 42% while giving equal performance and slightly better battery life. Assuming they were able to do the same with the Apple A5X which powers the iPad 3, this would mean that a Retina-capable chip would measure in at about 95mm2 or thereabouts. Or Apple could maintain the die size at roughly 120mm2 and use the additional space on the SOC for improvements in processing and graphical speed.

Conclusion

We can keep praying to the pixel pixies and lithium leprechauns to cheat physics and fit a Retina display in an iPad Mini but logic dictates that is just isn’t currently feasible in any manner which would be remotely usable.

We should be able to see a Retina-capable iPad mini in a year - or six months :p - given the technology available to Apple. Once there are enough iPhone 5s and iPad 4s out in the wild, it would behoove Apple to move the iPad mini onto Samsung’s 32nm process, clearing the way to a Retina display.

My Opinion

I think the first generation iPad mini is quite overpriced but it is done so that when the second generation mini’s bring twice the RAM and Retina display, they can incorporate them without raising the price.

Perceptively, starting at a high price and maintaining it is more palatable than starting lower and increasing. It’s almost like an early adopters entry fee. I genuinely believe that Apple has accounted for the price of future Retina displays in the pricing of first generation of iPad minis. Like the current iPad, where they make smaller margins on the 16GB versions, but charge $100 premium for the 32GB version (which requires $10 of additional NAND over 16GB) and $200 premium for the 64GB version (which requires an $30 of additional NAND over 16GB).

I am eagerly awaiting the second iteration of the iPad mini which should be everything the first generation was meant to be.
 
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Conclusion -

Despite after all your "math" we'll still see a Retina mini within 6 months with a typical Apple slogan like "Small just got bigger!" :rolleyes:
 
Two reasons why.

1) Apples determination to insure a high gross profit.

2) They now have a reason to offer the mini w/ retina at a higher price soon.
 
Ashin said:
But we already know Apple's bill of materials is at least 50% of the price for the iPad 3... :confused:

Why would a smaller version cost more?:rolleyes::apple:
Click to expand...

If it had double the screen resolution, it would require more processor power and a bigger battery.

It wouldn't be selling for $329
 
jabingla2810 said:
If it had double the screen resolution, it would require more processor power and a bigger battery.

It wouldn't be selling for $329
Click to expand...

According to the iPad 3 bill of materials the screen costs $10 more for retina (but remember this is a smaller screen so maybe just $5), and the processor about $10 more... battery maybe $10

So that's like $25?

Apple would rather make $25 more profit than satisfy it's customers...

Of course though, they are a business after all. Sugar coat it all you like, but we'll see a Retina iPad mini for the same cost within 6 months
 
Ashin said:
According to the iPad 3 bill of materials the screen costs $10 more for retina (but remember this is a smaller screen so maybe just $5), and the processor about $10 more... battery maybe $10

So that's like $25?

Apple would rather make $25 more profit than satisfy it's customers...

Of course though, they are a business after all. Sugar coat it all you like, but we'll see a Retina iPad mini for the same cost within 6 months
Click to expand...

If you see a retina iPad mini that soon it will be significantly thicker. You may not trust math but it's hard to work around physics.
 
poloponies said:
If you see a retina iPad mini that soon it will be significantly thicker. You may not trust math but it's hard to work around physics.
Click to expand...

I never get the whole thinner is better craz going on in the world. Thinner is not better, i want to be able to hold something in my hand, esp with something like a phone or a tablet, i dont want to too thing where I cant grip it
 
Very good summation by OP imo.

poloponies said:
If you see a retina iPad mini that soon it will be significantly thicker. You may not trust math but it's hard to work around physics.
Click to expand...

Agreed. Retina mini is inevitable, but battery/cost concerns means I really can't see it happening before Q4 '13.

Besides, despite the naysayers and, spec and cost wise, the unfavourable comparisons with certain other smaller tablets (spec wise, it compares unfavourably to my year old Tab 7.7*), Apple don't *need* to release a retina mini to be competitive. They absolutely do need to be at the cutting edge in the full sized line though, which they are.

*Which will be down the road the moment my mini arrives. Cyanogenmod10 is great, the screen is great, video is great, browsing is decent....but that's it. Android tablet apps are dog****, believe the hype.
 
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the supply chain is at maximum capacity

when factories are used to the new 7.9" screen size, they can start making retina available

completely new form factor
 
Ashin said:
On the contrary how do you know it doesn't exist?

Or do you just trust your "friend" Apple isn't lying to you? :rolleyes:
Click to expand...

So you are implying that Apple is withholding this "new technology" because they want to release it at a later time? :rolleyes:

I guess you haven't heard about the whole GF2 Dito technology debacle concerning their new screen technology as it is.

Know your stuff before you go shouting it out :rolleyes:
 
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