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128MB, 256MB, 512MB (x64, SR) 240-Pin DDR2 SDRAM UDIMM Features
DDR2 SDRAM UDIMM
MT4HTF1664AY – 128MB MT4HTF3264AY – 256MB MT4HTF6464AY – 512MB
Features
• 240-pin, unbuffered dual in-line memory module (UDIMM)
• Fast data transfer rates: PC2-3200, PC2-4200, PC2-5300, or PC2-6400
• 128MB (16 Meg x 64), 256MB (32 Meg x 64), 512MB (64 Meg x 64)
• VDD = VDDQ = 1.8V • VDDSPD = 1.7–3.6V • JEDEC-standard 1.8V I/O (SSTL_18-compatible) • Differential data strobe (DQS, DQS#) option • 4n-bit prefetch architecture • Multiple internal device banks for concurrent
operation
• Programmable CAS latency (CL) • Posted CAS additive latency (AL) • WRITE latency = READ latency - 1 tCK • Programmable burst lengths (BL): 4 or 8 • Adjustable data-output drive strength • 64ms, 8192-cycle refresh • On-die termination (ODT) • Serial presence detect (SPD) with EEPROM • Gold edge contacts • Single rank
Figure 1: 240-Pin UDIMM (MO-237 R/C C)
Module height 30.0mm (1.18.