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Spartan-3A DSP FPGA Family: DC and Switching Characteristics
DS610 (v3.0) October 4, 2010
www.xilinx.com
Product Specification
41
Block RAM Timing
Table 33:
Block RAM Timing
Symbol
Description
Speed Grade
Units
-5
-4
Min
Max
Min
Max
Clock-to-Output Times
T
RCKO_DOA_NC
When reading from block RAM, the delay from the active transition at
the CLK input to data appearing at the DOUT output
–
2.38
–
2.80
ns
T
RCKO_DOA
Clock CLK to DOUT output (with output register)
–
1.24
–
1.45
ns
Setup Times
T
RCCK_ADDR
Setup time for the ADDR inputs before the active transition at the CLK
input of the block RAM
0.40
–
0.46
–
ns
T
RDCK_DIB
Setup time for data at the DIN inputs before the active transition at the
CLK input of the block RAM
0.29
–
0.33
–
ns
T
RCCK_ENB
Setup time for the EN input before the active transition at the CLK input
of the block RAM
0.51
–
0.60
–
ns
T
RCCK_WEB
Setup time for the WE input before the active transition at the CLK input
of the block RAM
0.64
–
0.75
–
ns
T
RCCK_REGCE
Setup time for the CE input before the active transition at the CLK input
of the block RAM
0.34
–
0.40
–
ns
T
RCCK_RST
Setup time for the RST input before the active transition at the CLK
input of the block RAM
0.22
–
0.25
–
ns
Hold Times
T
RCKC_ADDR
Hold time on the ADDR inputs after the active transition at the CLK
input
0.09
–
0.10
–
ns
T
RCKC_DIB
Hold time on the DIN inputs after the active transition at the CLK input
0.09
–
0.10
–
ns
T
RCKC_ENB
Hold time on the EN input after the active transition at the CLK input
0.09
–
0.10
–
ns
T
RCKC_WEB
Hold time on the WE input after the active transition at the CLK input
0.09
–
0.10
–
ns
T
RCKC_REGCE
Hold time on the CE input after the active transition at the CLK input
0.09
–
0.10
–
ns
T
RCKC_RST
Hold time on the RST input after the active transition at the CLK input
0.09
–
0.10
–
ns
Clock Timing
T
BPWH
High pulse width of the CLK signal
1.56
–
1.79
–
ns
T
BPWL
Low pulse width of the CLK signal
1.56
–
1.79
–
ns
Clock Frequency
F
BRAM
Block RAM clock frequency
0
320
0
280
MHz
Notes:
1.
The numbers in this table are based on the operating conditions set forth in
Table 7
.