Description
The HYS72D256520GR–7–A are low profile versions of the standard Registered DIMM modules with 1.2” inch (30,48 mm) height for 1U Server Applications. The Low Profile DIMM versions are available as 256M × 72 (2GB). The memory array is designed with Double Data Rate Synchronous DRAMs for ECC applications. All control and address signals are re-driven on the DIMM using register devices and a PLL for the clock distribution. This reduces capacitive loading to the system bus, but adds one cycle to the SDRAM timing. A variety of decoupling capacitors are mounted on the PC board. The DIMMs feature serial presence detect based on a serial E2PROM device using the 2-pin I2C protocol. The first 128 bytes are programmed with configuration data and the second 128 bytes are available to the customer.

FEATUREs
• 184-pin Registered 8-Byte Dual-In-Line DDR SDRAM Module for “1U” PC, Workstation and Server main memory applications
• Two ranks 256M × 72 organization
• JEDEC standard Double Data Rate Synchronous DRAMs (DDR SDRAM) with a single + 2.5 V (± 0.2 V) power supply
• Built with DDR SDRAMs in 66-Lead TSOPII package
• Programmable CAS Latency, Burst Length, and Wrap Sequence (Sequential & Interleave)
• Auto Refresh (CBR) and Self Refresh
• All inputs and outputs SSTL_2 compatible
• Re-drive for all input signals using register and PLL devices.
• Serial Presence Detect with E2PROM
• Low Profile Modules form factor: 133.35 mm × 30.48 mm (1.2”) × 6.80 mm with stacked components)
• Based on Jedec standard reference card layout RawCard “N”
• Gold plated contacts