Datasheet

MCF5208 ColdFire
®
Microprocessor Data Sheet, Rev. 3
Electrical Characteristics
Freescale Semiconductor32
Figure 18. DDR Write Timing
7
This specification relates to the required hold time of today’s DDR memories. MEM_DATA[31:24] is relative to MEM_DQS[3],
MEM_DATA[23:16] is relative to MEM_DQS[2], MEM_DATA[15:8] is relative to MEM_DQS[1], and MEM_[7:0] is relative
MEM_DQS[0].
8
Data input skew is derived from each DQS clock edge. It begins with a DQS transition and ends when the last data line becomes
valid. This input skew must include DDR memory output skew and system level board skew (due to routing or other factors).
9
Data input hold is derived from each DQS clock edge. It begins with a DQS transition and ends when the first data line becomes
invalid.
SD_CLK
SD_CS
n, SD_WE,
DM3/DM2
D[31:24]/D[23:16]
A[13:0]
SD_RAS
, SD_CAS
CMD
ROW
DD1
DD5
DD4
COL
WD1 WD2 WD3 WD4
DD7
SD_DQS3/SD_DQS2
DD8
DD8
DD7
SD_CLK
DD3
DD2
DD6