tequila bomb

Apple A5 Teardown…

We had decapsulated the A5 a couple of days ago, but as you could see in those early pictures, you can’t tell much of a chip’s layout from the top metal – it’s all power and ground buses.  So we have to de-layer the chip down to a level where we can see the block layout of the chip; not an easy thing when there’s nine layers of metal!  In fact, these days it’s easier to go in from the back and remove the substrate silicon, and look at the gate level from below.  Then we can identify the circuit blocks that make up the full device.

[W]e’ve labeled the key blocks; the ARM cores are in the right half of the die, with ~4.5 Mb of cache memory each.  We can also see the USB interface at the top, and the DDR SDRAM interfaces at the bottom right, for the memory in the top part of the package-on-package.  Other I/O blocks are strewn around the edge of the die.

Interesting stuff.