Product Overview:

The Rambus Direct RDRAM™ is a general purpose high performance memory device suitable for use in a broad range of applications including computer memory, graphics, video, and any other application where high bandwidth and low latency are required.

The 128/144-Mbit Direct Rambus DRAMs (RDRAM®) are extremely high-speed CMOS DRAMs organized as 8M words by 16 or 18 bits.   The use of Rambus Signaling Level (RSL) technology permits 800MHz transfer rates while using conventional system and board design technologies.  Direct RDRAM devices are capable of sustained data transfers at 1.25 ns per two bytes (10ns per sixteen bytes).

The architecture of the Direct RDRAMs allows the highest sustained bandwidth for multiple, simultaneous randomly addressed memory transactions.  The separate control and data buses with independent row and column control yield over 95% bus efficiency.  The Direct RDRAM's thirty-two banks support up to four simultaneous transactions.

System oriented features for mobile, graphics and large memory systems include power management, byte masking, and x18 organization.  The two data bits in the x18 organization are general and can be used for additional storage and bandwidth or error correction.

Product Features:

• Highest sustained bandwidth per DRAM device
  • 1.6GB/s sustained data transfer rate
  • Separate control and data buses for maximized efficiency
  • Separate row and column control buses for easy scheduling and highest performance
  • 32 banks: four transactions can take place simultaneously at full bandwidth data rates
• Low latency features
  • Write buffer to reduce read latency
  • 3 precharge mechanisms for controller flexibility
  • Interleave transactions
• Advanced power management:
  • Multiple low power states allows flexibility in power consumption versus time to transition to active state
  • Power-down self-refresh
• Organization: 1Kbyte pages and 32 banks, x 16/18
  • x18 organization allows ECC configurations or increased storage/bandwidth
  • x16 organization for low cost applications
• Uses Rambus Signaling Level (RSL) for up to 800MHz operation