DOUBLE DATA RATE(DDR) SDRAM VDD = +2.5V ±0.2V, VDDQ = +2.5V ±0.2V • Bidirectional data strobe (DQS) transmitted/ received with data, i.e., source-synchronous data capture (x16 has two – one per byte) • Internal, pipelined double-data-rate (DDR) architecture; two data accesses per clock cycle • Differential clock inputs (CK and CK#) • Commands entered on each positive CK edge • DQS edge-aligned with data for READs; centeraligned with data for WRITEs • DLL to align DQ and DQS transitions with CK • Four internal banks for concurrent operation • Data mask (DM) for masking write data (x16 has two – one per byte) • Programmable burst lengths: 2, 4, or 8 • Auto precharge option • Auto Refresh and Self Refresh Modes • Longer lead TSOP for improved reliability (OCPL) • 2.5V I/O (SSTL_2 compatible)

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