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Spartan-3A DSP FPGA Family: DC and Switching Characteristics
DS610 (v3.0) October 4, 2010
www.xilinx.com
Product Specification
39
Table 30:
CLB Distributed RAM Switching Characteristics
Symbol
Description
Speed Grade
Units
-5
-4
Min
Max
Min
Max
Clock-to-Output Times
T
SHCKO
Time from the active edge at the CLK input to data appearing on
the distributed RAM output
–
1.44
–
1.72
ns
Setup Times
T
DS
Setup time of data at the BX or BY input before the active
transition at the CLK input of the distributed RAM
–0.07
–
–0.02
–
ns
T
AS
Setup time of the F/G address inputs before the active transition
at the CLK input of the distributed RAM
0.18
–
0.36
–
ns
T
WS
Setup time of the write enable input before the active transition at
the CLK input of the distributed RAM
0.30
–
0.59
–
ns
Hold Times
T
DH
Hold time of the BX and BY data inputs after the active transition
at the CLK input of the distributed RAM
0.13
–
0.13
–
ns
T
AH,
T
WH
Hold time of the F/G address inputs or the write enable input after
the active transition at the CLK input of the distributed RAM
0.01
–
0.01
–
ns
Clock Pulse Width
T
WPH
, T
WPL
Minimum High or Low pulse width at CLK input
0.88
–
1.01
–
ns
Table 31:
CLB Shift Register Switching Characteristics
Symbol
Description
Speed Grade
Units
-5
-4
Min
Max
Min
Max
Clock-to-Output Times
T
REG
Time from the active edge at the CLK input to data appearing on
the shift register output
–
4.11
–
4.82
ns
Setup Times
T
SRLDS
Setup time of data at the BX or BY input before the active
transition at the CLK input of the shift register
0.13
–
0.18
–
ns
Hold Times
T
SRLDH
Hold time of the BX or BY data input after the active transition at
the CLK input of the shift register
0.16
–
0.16
–
ns
Clock Pulse Width
T
WPH
, T
WPL
Minimum High or Low pulse width at CLK input
0.90
–
1.01
–
ns