Is a high performance HyperRAM controller really simpler than a normal DRAM controller? It's serial rather than parallel so you need higher frequency signals for the same bandwidth.
Yes, significantly so. However you saturate the bus with less effort (lower frequency, less wires), so perhaps the simplicity is due to a lower theoretical performance.
> First-generation HYPERRAM™ devices supported up to 166 MHz DDR clock frequency whereas as second-
generation devices that now support a clock frequency of 200 MHz have a peak data transfer rate of 0.4 GBps. [0]
