3 ms·
Can anyone weigh in on why at least some dozen MB were made available?
by DrNosferatu 2y ago
Can anyone weigh in on why at least some dozen MB were made available?
- DrNosferatu 2y ago*why not more SRAM?
- dgacmu 2y agocost and power and latency. The rp2040 is fabbed at 40nm. It's _really_ expensive to fab on things closer to the cutting edge, and the volume of rp2040/2350 sales simply isn't enough to justify it. (Also, it's harder to design and ends up binding you more tightly to a fab). At 40nm, adding 1MB of SRAM would literally make the chip more than 2x larger, which would increase the cost by quite a bit -- and probably make the SRAM slower. You can see a die shot / layout here: https://www.raspberrypi.com/products/rp2040/ https://www.raspberrypi.com/products/rp2040/ Notice how much of the area is already SRAM. That's hefty. It would make the chip more expensive without much of a corresponding return on applications enabled. People who need more SRAM can add an external SRAM if they need it.