HY5DU28422BT Datasheet, PDF (31/33 Pages) Hynix Semiconductor – 128M-S DDR SDRAM

HY5DU28422B(L)T
HY5DU28822B(L)T
14. DQS, DM and DQ input slew rate is specified to prevent double clocking of data and preserve setup and hold times. Signal
transitions through the DC region must be monotonic.
15. tDAL = (tDPL / tCK ) + (tRP / tCK ). For each of the terms above, if not already an integer, round to the next highest integer.
tCK is equal to the actual system clock cycle time.
Example: For DDR266B at CL=2.5 and tCK = 7.5 ns,
tDAL = (15 ns / 7.5 ns) + (20 ns / 7.5 ns) = (2.00) + (2.67)
Round up each non-integer to the next highest integer: = (2) + (3), tDAL = 5 clocks
16. For the parts which do not has internal RAS lockout circuit, Active to Read with Auto precharge delay should be
tRAS - (BL/2) x tCK.
17. tHZ and tLZ transitions occur in the same access time windows as valid data trasitions. These parameters are not referenced
to a specific voltage level but specify when the device output is no longer driving (HZ), or begins driving (LZ).
Rev. 0.3/May. 02
31