Abstract

It is time to reconsider unifying logic and memory. Since most of the transistors on this merged chip will be devoted to memory, it is called ‘intelligent RAM’. IRAM is attractive because the gigabit DRAM chip has enough transistors for both a powerful processor and a memory big enough to contain whole programs and data sets. It contains 1024 memory blocks each 1kb wide. It needs more metal layers to accelerate the long lines of 600mm/sup 2/ chips. It may require faster transistors for the high-speed interface of synchronous DRAM. Potential advantages of IRAM include lower memory latency, higher memory bandwidth, lower system power, adjustable memory width and size, and less board space. Challenges for IRAM include high chip yield given processors have not been repairable via redundancy, high memory retention rates given processors usually need higher power than DRAMs, and a fast processor given logic is slower in a DRAM process.