FBD Channel Interface
Figure 2-1. Delays Through an AMB
TDimm_Cmd_Delay
TAMB_Cmd_Delay
SET
CLR
SET
CLR
D
Q
Q
D
Q
Q
DDR Command
SB Frame Clock
DRAM Clock
DDR IO CMD
Clock
DRAMs
SET
CLR
SET
Q
Q
D
Q
Q
D
DRAM Data
Data
DQS
CLR
Buffer/FIFO
NB Frame Clock
TDimm_Data_Delay
TAMB_Data_Delay
The definition for terms used in the are given below.
UI
This is the unit interval on the FBD link. This is same as the
period of the FBD link bit-rate clock.
NB:
SB:
Northbound
Southbound
TRead_Latency: DRAM Parameter. TCAS + TAdditive_Latency
TAMB_Cmd_Delay
TAMB_Data_Delay
TDimm_Cmd_Delay
This value is very specific to an AMB implementation. This is the
time it takes for the command to be transferred from the FBD
receiver to the DDR I/O Cluster. This includes any differences
between the FBD frame clock and the DDR I/O clock that latches
the command into the DDR I/O cluster. This can be different for
different DRAM frequencies.
This value is very specific to an AMB implementation. This is the
minimum time it takes for the data that is returned from the
DRAMs to be transferred from the DDR I/O cluster to the FBD I/
O for transmission on the link. This includes any buffering and
clocking delays for the data within the chip. This can be
different for different DRAM frequencies.
This includes the delays for the command through the DDR I/O
cluster, differences between DDR I/O CMD Clock and DRAM
clock, any routing delays for the clock and command on the
22
Intel® 6400/6402 Advanced Memory Buffer Datasheet
INTEL [ INTEL ]
