Intel IXP46X Computer Hardware User Manual


 
Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
February 2007 HDD
Document Number: 305261, Revision: 004 83
DDR-SDRAM—Intel
®
IXP45X and Intel
®
IXP46X Product Line of Network Processors
Figure 33. DDR-Data-to-DQS-Write Timing Parameters
Table 31. DDR Data to DQS Write Timing Parameters
Symbol Parameter Min Max Units Notes
T
1
IXP45X/IXP46X network processors output valid for data
group signals prior to the transition of DQS
1.0 ns 1
T
2
IXP45X/IXP46X network processors output hold time for
data group signals after the transition of DQS
1.0 ns 1
T
3
Required data group input setup time at DDR memory
device
0.5 ns 1
T
4
Required data group input hold time at DDR memory
device
0.5 ns 1
T
5
Allowable setup time difference between IXP45X/IXP46X
network processors data group output and setup time
required by DDR memory device
0.5 ns 1
T
6
Allowable hold time difference between IXP45X/IXP46X
network processors data group output and hold time
required by DDR memory device
0.5 ns 1
Notes:
1. Data group signals consist of DDRI_DM[4:0], DDRI_DQ[31:0], and DDRI_CB[7:0]
Figure 34. DDR-Clock-to-DQS-Write Timing Parameters
DQS
Data Valid
T
1
T
2
T
3
T
4
T
6
T
5
Data
B3990-001
DDR_M_CLK
T
3
T
4
T
1
T
2
T
6
T
5
DQS
B3991-001