2 ms·

*why not more SRAM?

• dgacmu 2y ago
  cost 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.