Main View
Part Number: 2528157R512 MB 667 MHZ DDR2 SODIMM Memory Module (CRU/EURP)

Example of DDR2 memory module

DDR2 memory modules have basically the same dimensions as the DDR modules, but because of different voltages and pin configurations, DDR2 modules have a different "key" or notch in their connector to prevent them from being plugged into an incompatible socket. DDR2 memory modules will only fit in systems and motherboards designed to specifically support DDR2 memory. A DDR2 SODIMM will not fit in the DDR memory slot.

DDR2 modules use a 1.8 V power supply, providing a big power saving over the 2.5 V DDR modules. DDR2 modules for notebook computers require up to 65% less voltage than DDR, thus improving battery life. The extended battery life can improve mobility and productivity.

DDR2 memory chips main features are:

  • JEDEC standard Power Supply
  • VDD = VDDQ = 1.8 V +/-0.1 V
  • Programmable CAS Latency 3, 4, and 5
  • Programmable Additive Latency: 0, 1, 2, 3, and 4
  • Write Latency = Read Latency -1
  • Programmable Burst Length: 4 and 8
  • Programmable Sequential / Interleave Burst
  • OCD (Off-chip Driver Impedance Adjustment)
  • ODT (On-Die Termination)
  • 4 bit prefetch architecture
  • Data-Strobe: Bidirectional, Differential
  • Weak Strength Data-Output Driver Option
  • Auto-Refresh and Self-Refresh
  • Power Saving Power-Down modes
  • 7.8µs Maximum Average Periodic Refresh Interval