R
Clock Buffer/Multiplexer Switching Characteristics
Table 23: Clock Distribution Switching Characteristics
Maximum
Description
Symbol
-4 Speed Grade
Units
Global clock buffer (BUFG, BUFGMUX, BUFGCE) I input to O-output
delay
T
1.46
ns
GIO
Global clock multiplexer (BUFGMUX) select S-input setup to I0 and I1
inputs. Same as BUFGCE enable CE-input
T
0.63
311
ns
GSI
Frequency of signals distributed on global buffers (all sides)
F
MHz
BUFG
18 x 18 Embedded Multiplier Timing
Table 24: 18 x 18 Embedded Multiplier Timing
-4 Speed Grade
Symbol
Description
Min
Max
Units
Combinatorial Delay
T
Combinatorial multiplier propagation delay from the A and B inputs to
the P outputs, assuming 18-bit inputs and a 36-bit product (AREG,
BREG, and PREG registers unused)
MULT
(1)
-
4.88
ns
Clock-to-Output Times
T
Clock-to-output delay from the active transition of the CLK input to valid
data appearing on the P outputs when using the PREG register
MSCKP_P
-
-
1.10
ns
ns
(2)
T
T
Clock-to-output delay from the active transition of the CLK input to valid
data appearing on the P outputs when using either the AREG or BREG
MSCKP_A
MSCKP_B
4.97
(3)
register
Setup Times
T
Data setup time at the A or B input before the active transition at the
CLK when using only the PREG output register (AREG, BREG
registers unused)
MSDCK_P
3.98
-
ns
(2)
T
T
Data setup time at the A input before the active transition at the CLK
when using the AREG input register
MSDCK_A
MSDCK_B
0.23
0.39
-
-
ns
ns
(3)
Data setup time at the B input before the active transition at the CLK
(3)
when using the BREG input register
Hold Times
T
Data hold time at the A or B input before the active transition at the CLK
when using only the PREG output register (AREG, BREG registers
unused)
MSCKD_P
-0.97
(2)
T
T
Data hold time at the A input before the active transition at the CLK
when using the AREG input register
MSCKD_A
MSCKD_B
0.04
0.05
(3)
Data hold time at the B input before the active transition at the CLK
(3)
when using the BREG input register
DS635 (v2.0) September 9, 2009
www.xilinx.com
Product Specification
22
XILINX [ XILINX, INC ]
