k4h560838e Samsung Semiconductor, Inc., k4h560838e Datasheet - Page 19

• Manufacturer Part Number: k4h560838e
• Description: Ddr Sdram 256mb E-die X4, X8
• Manufacturer: Samsung Semiconductor, Inc.

DDR SDRAM 256Mb E-die (x4, x8)
Component Notes
17. For CK & CK slew rate t1.0 V/ns
18. These parameters guarantee device timing, but they are not necessarily tested on each device. They may be guaranteed by
19. Slew Rate is measured between VOH(ac) and VOL(ac).
20. Min (tCL, tCH) refers to the smaller of the actual clock low time and the actual clock high time as provided to the device (i.e. this
21. tQH = tHP - tQHS, where:
22. tDQSQ
23. tDAL = (tWR/tCK) + (tRP/tCK)
device design or tester correlation.
Consists of data pin skew and output pattern effects, and p-channel to n-channel variation of the output drivers for any given cycle.
value can be greater than the minimum specification limits for tCL and tCH).....For example, tCL and tCH are = 50% of the
period, less the half period jitter (tJIT(HP)) of the clock source, and less the half period jitter due to crosstalk (tJIT(crosstalk)) into
the clock traces.
case pull-in of DQ on the next transition, both of which are, separately, due to data pin skew and output pattern effects, and p-
channel to n-channel variation of the output drivers.
For each of the terms above, if not already an integer, round to the next highest integer. Example: For DDR266B at CL=2.5 and
tCK=7.5ns tDAL = (15 ns / 7.5 ns) + (20 ns/ 7.5ns) = (2) + (3)
tDAL = 5 clocks
tHP = minimum half clock period for any given cycle and is defined by clock high or clock low (tCH, tCL). tQHS accounts for 1) The
pulse duration distortion of on-chip clock circuits; and 2) The worst case push-out of DQS on one tansition followed by the worst
Rev. 1.3 April. 2005
DDR SDRAM