EDS2504ACTA Datasheet, PDF (14/51 Pages) Elpida Memory – 256M bits SDRAM

EDS2504ACTA/08ACTA/16ACTA, EDS2504APTA/08APTA/16APTA
DQM, UDQM and LDQM (input pins)
DQM controls input/output buffers. In 16M × 16 products, UDQM and LDQM control upper byte (DQ8 to DQ15) and
lower byte (DQ0 to DQ7).
Read operation: If DQM is High, the output buffer becomes High-Z. If the DQM is Low, the output buffer becomes
Low-Z. (The latency of DQM during reading is 2 clocks.)
Write operation: If DQM is High, the previous data is held (the new data is not written). If DQM is Low, the data is
written. (The latency of DQM during writing is 0 clock.)
DQ0 toDQ15 (input/output pins)
Data is input to and output from these pins (DQ0 to DQ3; EDS2504AC/AP , DQ0 to DQ7; EDS2508AC/AP, DQ0 to
DQ15; EDS2516AC/AP).
VDD, VSS, VDDQ, VSSQ (Power supply)
VDD and VSS are power supply pins for internal circuits. VDDQ and VSSQ are power supply pins for the output
buffers.
Data Sheet E0110E30 (Ver. 3.0)
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