
Virtex-E 1.8 V Extended Memory Field Programmable Gate Arrays
Module 3 of 4
DS025-3 (v3.0) March 21, 2014
14
R
— OBSOLETE — OBSOLETE — OBSOLETE — OBSOLETE —
CLB Distributed RAM Switching Characteristics
Description(1)
Symbol
Speed Grade
Units
Min
-8
-7
-6
Sequential Delays
Clock CLK to X/Y outputs (WE active) 16 x 1 mode
TSHCKO16
0.67
1.38
1.5
1.7
ns, max
Clock CLK to X/Y outputs (WE active) 32 x 1 mode
TSHCKO32
0.84
1.66
1.9
2.1
ns, max
Shift-Register Mode
Clock CLK to X/Y outputs
TREG
1.25
2.39
2.9
3.2
ns, max
Setup and Hold Times before/after Clock CLK
F/G address inputs
TAS/TAH
0.19 / 0
0.38 / 0
0.42 / 0
0.47 / 0
ns, min
BX/BY data inputs (DIN)
TDS/TDH
0.44 / 0
0.87 / 0
0.97 / 0
1.09 / 0
ns, min
SR input (WE)
TWS/TWH
0.29 / 0
0.57 / 0
0.7 / 0
0.8 / 0
ns, min
Clock CLK
Minimum Pulse Width, High
TWPH
0.96
1.9
2.1
2.4
ns, min
Minimum Pulse Width, Low
TWPL
0.96
1.9
2.1
2.4
ns, min
Minimum clock period to meet address write cycle time
TWC
1.92
3.8
4.2
4.8
ns, min
Shift-Register Mode
Minimum Pulse Width, High
TSRPH
1.0
1.9
2.1
2.4
ns, min
Minimum Pulse Width, Low
TSRPL
1.0
1.9
2.1
2.4
ns, min
Notes:
1.
A Zero “0” Hold Time listing indicates no hold time or a negative hold time. Negative values can not be guaranteed “best-case”, but
if a “0” is listed, there is no positive hold time.
Figure 3: Dual-Port Block SelectRAM
WEB
ENB
RSTB
CLKB
ADDRB[#:0]
DIB[#:0]
WEA
ENA
RSTA
CLKA
ADDRA[#:0]
DIA[#:0]
DOA[#:0]
DOB[#:0]
RAMB4_S#_S#
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