Datasheet

DTM65523C
4 GB, 240-Pin DDR2 FB-DIMM
Document 06026, Revision A, 29-Sep-10, Dataram Corporation © 2010 Page 9
Advanced Memory Buffer FBD Timing/Electrical
Parameter Symbol MIN MAX Units
EI Assertion Pass-Through Timing
tEI PROPAGATE
4 CLKs
EI Deassertion Pass-Through Timing
tEID
tBitlock CLKs
EI Assertion Duration
tEI
100 CLKs
Bit Lock Interval
tBITLOCK
119 Frames
Frame Lock Interval
tFRAMELOCK
154 Frames
Advanced Memory Buffer Latency Parameters
Parameter Symbol MIN MAX Units
CMD to Data Latency (Data Rate = 533)
tC2D_AMB 20.3 25.1 ns
Resample Delay
tRESAMPLE_AMB_NB,
RESAMPLE_AMB_SB
0.9 2.2 ns
Resync Delay
tRESYNC_AMB_NB,
tRESYNC_AMB_SB
2.3 3.9 ns
Notes:
1. t
C2D_AMB is the measured delay at AMB balls between the center of the first UI command frame on primary southbound lane 8
(AMB balls U29 and U28), and the center of the first UI of return on primary northbound lane 0 (AMB balls U1 and U2) - CL
(DRAM CAS latency) value * frame clock period - AL (DRAM additional latency) value * frame clock period. This definition
assumes that SB lane 8 is the latest lane to arrive at the AMB balls. This will typically be the case since SB lane 8 is the
longest SB lane on FBDIMMs. If, due to large lane-to-lane skew at the DIMM gold finger, another lane is the latest lane to
arrive at the AMB balls, this other lane must be used instead for the t
C2D_AMB measurement.
2. t
RESAMPLE_AMB_NB is the measured delay at AMB balls between the center of the first UI of a frame on secondary northbound
lane 0 (AMB balls V4 and V5), and the center of the first UI of the same frame on primary northbound lane 0 (AMB balls U1
and U2).
3. t
RESAMPLE_AMB_SB is the measured delay at AMB balls between the center of the first UI of a frame on primary southbound lane
8 (AMB balls U29 and U28), and the center of the first UI of the same frame on secondary southbound lane 8 (AMB balls Y26
and W26).
4. t
RESYNC_AMB_NB is the measured delay at AMB balls between the center of the first UI of a frame on secondary northbound lane
0 (AMB balls V4 and V5), and the center of the first UI of the same frame on primary northbound lane 0 (AMB balls U1 and
U2).
5. t
RESYNC_AMB_SB is the measured delay at AMB balls between the center of the first UI of a frame on primary southbound lane 8
(AMB balls U29 and U28), and the center of the first UI of the same frame on secondary southbound lane 8 (AMB balls Y26
and W26).