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Banned
Well, lets continue then:
I am not sure which of the tow dies inside the Hollywood package is the eDRAM and which one is the graphics chip. Most people think that vegas is the graphics chip and that napa is the edRAM, but for now lets consider both of them as possible candidates for being the eDRAM.
Now we know that these die measure:
vegas 9mm x 8mm = 72mm2
napa 13.5mm x 7mm = 94.5mm2
Now, there is a little problem with the statement made by Maxcosnole, perhaps, that the eDRAM has 24MBytes of 1T-SRAM(if you read most of what I have post here then ypu know that the eDRAM should be UX6D, but will make use of this example for the exceptic ones), and thats that neither vegas, nor napa have enough space for holding 24MBytes of 1T-SRAM
It could take me forever to try to provide the links with the information about the die size and the quantity of memory that each of the different types of Mosys 1T-SRAM macros provide, not to mention that since only 1T-MIM is available at 90nm and further I would have to do some calculations at 90nm for the rest of the other mosys macros; thankfully we have wikipedia:
http://en.wikipedia.org/wiki/1T-SRAM
Just check the table provided there and just use the full macros for calculations(with overhead).- 1T-SRAM Cell sizes (μm²/bit or mm²/Mbit)
1T-SRAM with overhead can hold 1MBit in 1.1mm2
which means that it can hold 1MBit/8bit MBytes in 1.1mm2
1T-SRAM with overhead can hold 0.125MBytes in 1.1mm2
For 24MBytes that would require?
24MBytes * 1.1mm2 / 0.125MBytes = 211.2mm2
What the!!????
Neither vegas(72mm2) not napa(94.5mm2) have enough room for that, even considering both dies as eDRAM would be enough
Now lets consider
1T-SRAM-Q with overhead
it can hold 1MBit in 0.55mm2
For 24MBytes that would require?
24MBytes * 0.55mm2 / 0.125MBytes = 105.6mm2
Again, none of the two dies have enough room for that.
That leaves us with 1T-MIM, but since NEC is the manufacturer and not TSMC, we will use the UX6D macro
if you have read all the information I provided about this macro, then you should know by now that it can hold as much as 1MBit in 0.22mm2, that´s 0.125MBytes in 0.22mm2
Then for 24MBytes?
24MBytes * 0.22mm2 / 0.125MBytes = 42.24mm2
So, as you can see, this one is the only choice, and not just that, since both vegas and napa have enough room for 24MBytes at the grade that we would have 29.76mm2 free space for vegas or 52.26mm2 for napa for other things.
I am not sure which of the tow dies inside the Hollywood package is the eDRAM and which one is the graphics chip. Most people think that vegas is the graphics chip and that napa is the edRAM, but for now lets consider both of them as possible candidates for being the eDRAM.
Now we know that these die measure:
vegas 9mm x 8mm = 72mm2
napa 13.5mm x 7mm = 94.5mm2
Now, there is a little problem with the statement made by Maxcosnole, perhaps, that the eDRAM has 24MBytes of 1T-SRAM(if you read most of what I have post here then ypu know that the eDRAM should be UX6D, but will make use of this example for the exceptic ones), and thats that neither vegas, nor napa have enough space for holding 24MBytes of 1T-SRAM
It could take me forever to try to provide the links with the information about the die size and the quantity of memory that each of the different types of Mosys 1T-SRAM macros provide, not to mention that since only 1T-MIM is available at 90nm and further I would have to do some calculations at 90nm for the rest of the other mosys macros; thankfully we have wikipedia:
http://en.wikipedia.org/wiki/1T-SRAM
Just check the table provided there and just use the full macros for calculations(with overhead).- 1T-SRAM Cell sizes (μm²/bit or mm²/Mbit)
1T-SRAM with overhead can hold 1MBit in 1.1mm2
which means that it can hold 1MBit/8bit MBytes in 1.1mm2
1T-SRAM with overhead can hold 0.125MBytes in 1.1mm2
For 24MBytes that would require?
24MBytes * 1.1mm2 / 0.125MBytes = 211.2mm2
What the!!????
Neither vegas(72mm2) not napa(94.5mm2) have enough room for that, even considering both dies as eDRAM would be enough
Now lets consider
1T-SRAM-Q with overhead
it can hold 1MBit in 0.55mm2
For 24MBytes that would require?
24MBytes * 0.55mm2 / 0.125MBytes = 105.6mm2
Again, none of the two dies have enough room for that.
That leaves us with 1T-MIM, but since NEC is the manufacturer and not TSMC, we will use the UX6D macro
if you have read all the information I provided about this macro, then you should know by now that it can hold as much as 1MBit in 0.22mm2, that´s 0.125MBytes in 0.22mm2
Then for 24MBytes?
24MBytes * 0.22mm2 / 0.125MBytes = 42.24mm2
So, as you can see, this one is the only choice, and not just that, since both vegas and napa have enough room for 24MBytes at the grade that we would have 29.76mm2 free space for vegas or 52.26mm2 for napa for other things.