JEDEC Updates The High Bandwidth Memory (HBM) Standard
The new JESD235A standard leverages Wide I/O and TSV technologies to support up to 8 GB per device at speeds up to 256 GB/s. This bandwidth is delivered across a 1024-bit wide device interface that is divided into 8 independent channels on each DRAM stack. The standard supports 2-high, 4-high and 8-high TSV stacks of DRAM at full bandwidth to allow systems flexibility on capacity requirements from 1 GB - 8 GB per stack.
Additional improvements in the recent update include a new pseudo channel architecture to improve effective bandwidth, and clarifications and enhancements to the test features. JESD235A also defines a new feature to alert controllers when DRAM temperatures have exceeded a level considered acceptable for reliable operation so that the controller can take appropriate steps to return the system to normal operation.