A4 Teardown: "Nothing Revolutionary Here"

[Paul Daniel Ash]

A dissection of the A4 chip Apple designed for the iPad reveals that it's fairly conventional, incorporating a single core CPU - possibly the same one used in the iPhone 3GS - and some DRAM in a triple-layer "package-on-package" (PoP) design. Because the system-on-a-chip included the core and memory on a single piece of silicon, though, heroic measures were needed to look inside, including X-raying, soaking it in an acid bath and using a grinder to cut into the A4.

The guys at iFixit have done methodical teardowns of everything from cameras to guitars to mopeds. They did one on Apple's newest device on Saturday, revealing elegant engineering and a fancy case design, but nothing extraordinary. One black box remained, though: Apple's homegrown A4 system-on-a-chip. The iFixit guys had done a crude dissection of the iPhone's CPU with a band-saw back in 2007, but for this job they needed more advanced techniques, so they went to Chipworks, which does reverse engineering and patent protection work for major Silicon Valley manufacturers.

First, the A4 was X-rayed from the bottom and sides, showing the fine wirebond interconnects between the three layers. Then, the chip was dipped in acid to remove the ceramic outer layer, and was slowly ground down to reveal each individual die. The two DRAM modules had Samsung markings on them, as expected, but the CPU itself was unmarked. This indicated to iFixit's Kyle Wiens that "Apple is in firm control of the semiconductor design," rather than it being a result of Samsung engineering as is the iPhone 3GS CPU.

The analysis supported clues that ZodTTD already identified from his dump of the iPad's I/O registry tree, indicating that the A4 is indeed a single-core processor. This strengthens the case that the CPU is a Cortex-A8, rather than a Cortex-A9 as had been theorized. The GPU can't be conclusively identified from looking at the logic, but based on benchmarks it's believed to be a PowerVR SGX 535.

The conclusion? "There's not much revolutionary here," Kyle Wiens wrote, noting the A4 isn't all that different from the Samsung processor Apple uses in the iPhone. Only the power characteristics seem to have changed significantly, with the SoC drawing about 2.5 watts on average to give the iPad its 10 hour battery life.

image via iFixit

[z3r01]

yea thats nice

[Zeal]

Put it in the Microwave

[iphone?3gs]

whether its revolutionary or not ppl are still gonna buy it.... including me anytime soon ..... they never said the a4 chip was revolutionary they said the whole device on its own....

[dale1v]

lol.

[rel1215]

the teardown also revealed that the iPad only has 256 MB of RAM. That was the most shocking thing to me. Same RAM as the 3gs.

[rickybobby]

the teardown also revealed that the ipad only has 256 mb of ram. That was the most shocking thing to me. Same ram as the 3gs.

is that right so this new iphone might run the same or maybe a little bit more ram

[Bluprint]

i really like the ipad but this news is not comforting at all. Specs are so below average i don't know what to think.... I might consider returning it if something better comes up within the the next week or so.

[rickybobby]

i really like the ipad but this news is not comforting at all. Specs are so below average i don't know what to think.... I might consider returning it if something better comes up within the the next week or so.

don't return it bro its a very nice piece of tech dont let this get u down

[lolcats1]

NOTHING REVOLUTIONARY

yep, that's apple for you

[kickerman65]

Revolutionary or not i love mine. It surfs fast, its quick, and it brings me joy. Thats all i can ask. I knew what it was supposed to be when i bought it and it does a great job at it.

[sziklassy]

This is one of the main reasons I am waiting for the next gen iphone before even considering one of these. I expect them to beef up the iphone to 1ghz as well... there are just too many competitors that have already done that. Reading a book on the thing doesn't really appeal to me anyway, not does watching a movie. I have my TV for that LOL.

[Bluprint]

thnx rickybobby for the heads up. I was just expecting a lot more from apple, but other than that I'm very happy with it.

[whereswaldo]

cool, but will it blend?

[riku98523]

The A4 processor is the biggest fail about the ipad because they marketed it as "amazing" when in reality its a cheap processing unit that only runs at 1GHz and takes over the graphics as well. 10 Years ago when you bought a Macintosh or a windows PC you at least had an on board graphics chip. A4 is fail but I'm sure its enough to run the ipad and all its features at decent speeds.

[Poseidon79]

The integration of the graphics processor actually helps to increase the battery life... the graphics are still amazing and the overall speed of the device is unmatched. Whats the problem?!

[hollow0]

is that right so this new iphone might run the same or maybe a little bit more ram

Hopefully the new iPhone will have much more RAM. The current iPhone 3GS already has 256 i believe. That HTC HD3 has 1GB of RAM...Apple needs to compete in a BIG way. Match it!

[MalayZN]

omg only 256....... how the hell are people going to truly multitask with that little amount of memory...... especially if you run a game at the same time.... I hope the new iphone has at least 512 to 1gb..... ya I'm greedy.... haha

[Poseidon79]

omg only 256....... how the hell are people going to truly multitask with that little amount of memory...... especially if you run a game at the same time.... I hope the new iphone has at least 512 to 1gb..... ya I'm greedy.... haha

My iPad boot up with the same free memory as my 3GS.. about 130MB and I can run 3 or 4 apps at the same time with no lag. I don't foresee a problem here.

[sami4021]

Byt if they really want to
compete, why not give the new iphone more ram. Hey faster is better. And with 4.0 coming out, its going to
need it