ARM CSS 2 platform adds LPDDR6 support at 12,800 Mbps on mobiles: up to 77% more bandwidth than LPDDR5X

As we saw in the review of the new ARM CSS for Mobile 2 architecture, ARM has updated the memory controller of its platform to add native memory support LPDDR6.

This new controller uses four 24-bit channels capable of operating with LPDDR6 memories at speeds of up to 12,800 MT/s, reaching a theoretical bandwidth of 136 GB/s. This supposes a 77% improvement compared to the 76.8 GB/s offered by the previous generation through four 16-bit channels with LPDDR5X memory at 9,600 MT/s.

77% more bandwidth and new SI L2 interconnection system

This extra bandwidth, according to ARM, will bring improvements in local AI processing, a technology that all companies have rushed to embrace and focus their products towards it.

Along with the controller, the platform debuts the SI L2 interconnection system instead of the previous SI L1. This technology connects the CPU and GPU cluster to a 16 MB shared SLC cache.

These 16 MB are not distributed as a single block, but rather are divided into multiple nodes within each memory channel. In this way, according to ARM, memory access latency from the CPU is reduced by up to 45%.

Although it seems that manufacturers like Apple will still be stuck on LPDDR5 due to current memory costs. Companies like CXMT have already begun mass production of LPDDR6 chips, and it is clear that new chips and designs based on ARM’s CSS 2 platform will take advantage of this new technology.