Revision 1.26 – April 25, 2007
440EP – PPC440EP Embedded Processor
Data Sheet
Note: The timing data in the following tables is based on simulation runs using Einstimer.
Table 19. I/O Timing—DDR SDRAM T
DS
Notes:
1. All of the DQS signals are referenced to MemClkOut0(0).
2. Clock speed is 133MHz.
3. The TDS values in the table include 3/4 of a cycle at 133MHz (7.5ns x 0.75 = 5.625 ns).
4. To obtain adjusted values for lower clock frequencies, subtract 5.625 ns from the values in the table and add 3/4 of the cycle
time for the lower clock frequency (TDS - 5.625 + 0.75TCYC).
TDS (ns)
Signal Name
Minimum
5.76
Maximum
5.86
DQS0
DQS1
DQS2
DQS3
DQS8
5.78
5.91
5.82
5.90
5.79
5.89
5.75
5.88
Table 20. I/O Timing—DDR SDRAM T , T , and T
SK SA
HA
Notes:
1. Clock speed is 133MHz. TSK is referenced to MemClkOut0(0). TSA and THA are referenced to MemClkOut0(90).
2. To obtain adjusted TSA values for lower clock frequencies, use 3/4 of the cycle time for the lower clock frequency and subtract
TSK maximum (0.75TCYC - TSKmax).
3. To obtain adjusted THA values for lower clock frequencies, use 1/4 of the cycle time for the lower clock frequency and add
TSK minimum (0.25TCYC + TSKmin).
TSK (ns)
TSA (ns)
THA (ns)
Signal Name
Minimum
0.11
Maximum
0.32
Minimum
5.31
Minimum
1.99
MemAddr00:12
BA0:1
0.07
0.31
5.32
1.95
BankSel0:3
ClkEn0:3
CAS
0.05
0.25
5.38
1.93
0.07
0.28
5.35
1.95
0.05
0.31
5.32
1.93
RAS
0.05
0.28
5.35
1.93
WE
0.08
0.22
5.41
1.96
Table 21. I/O Timing—DDR SDRAM T and T
SD
HD
Notes:
1. TSD and THD are measured under worst case conditions.
2. Clock speed for the values in the table is 133MHz.
3. The time values in the table include 1/4 of a cycle at 133MHz (7.5ns x 0.25 = 1.875 ns).
4. To obtain adjusted TSD and THD values for lower clock frequencies, subtract 1.875 ns from the values in the table and add
1/4 of the cycle time for the lower clock frequency (e.g., TSD - 1.875 + 0.25TCYC).
TSD (ns)
THD (ns)
Signal Names
MemData00:07, DM0
MemData08:15, DM1
MemData16:23, DM2
MemData24:31, DM3
ECC0:7, DM8
Reference Signal
DQS0
1.795
1.775
1.745
1.765
1.685
1.866
1.865
1.862
1.864
1.857
DQS1
DQS2
DQS3
DQS8
74
AMCC Proprietary
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
