XC3SD1800A-4CS484I Xilinx Inc, XC3SD1800A-4CS484I Datasheet - Page 46

• Manufacturer Part Number: XC3SD1800A-4CS484I
• Description: FPGA Spartan®-3A Family 1.8M Gates 37440 Cells 667MHz 90nm Technology 1.2V 484-Pin LCSBGA
• Manufacturer: Xilinx Inc

Specifications of XC3SD1800A-4CS484I

• Package: 484LCSBGA
• Family Name: Spartan®-3A
• Device Logic Units: 37440
• Device System Gates: 1800000
• Maximum Internal Frequency: 667 MHz
• Typical Operating Supply Voltage: 1.2 V
• Maximum Number Of User I/os: 309
• Ram Bits: 1548288

Table 37: Switching Characteristics for the DLL (Cont’d)
Digital Frequency Synthesizer (DFS)
Table 38: Recommended Operating Conditions for the DFS
DS610 (v3.0) October 4, 2010
Product Specification
Notes:
1.
2.
3.
4.
5.
Notes:
1.
2.
3.
4.
5.
Delay Lines
DCM_DELAY_STEP
Input Frequency Ranges
F
Input Clock Jitter Tolerance
CLKIN_CYC_JITT_FX_LF
CLKIN_CYC_JITT_FX_HF
CLKIN_PER_JITT_FX
CLKIN
The numbers in this table are based on the operating conditions set forth in
Indicates the maximum amount of output jitter that the DCM adds to the jitter on the CLKIN input.
For optimal jitter tolerance and faster lock time, use the CLKIN_PERIOD attribute.
Some jitter and duty-cycle specifications include 1% of input clock period or 0.01 UI. For example, the data sheet specifies a maximum jitter
of ±[1% of CLKIN period + 150]. Assume the CLKIN frequency is 100 MHz. The equivalent CLKIN period is 10 ns and 1% of 10 ns is 0.1 ns
or 100 ps. According to the data sheet, the maximum jitter is ±[100 ps + 150 ps] = ±250 ps, averaged over all steps.
The typical delay step size is 23 ps.
DFS specifications apply when either of the DFS outputs (CLKFX or CLKFX180) are used.
If both DFS and DLL outputs are used on the same DCM, follow the more restrictive CLKIN_FREQ_DLL specifications in
CLKIN input jitter beyond these limits may cause the DCM to lose lock.
The DCM specifications are guaranteed when both adjacent DCMs are locked.
To support double the maximum effective F
clock frequency by two as it enters the DCM.
Symbol
CLKIN_FREQ_FX
Symbol
(5)
(2)
Finest delay resolution, averaged over all steps
(3)
Frequency for the CLKIN input
Cycle-to-cycle jitter at the
CLKIN input, based on CLKFX
output frequency
Period jitter at the CLKIN input
CLKIN
Description
limit, set the CLKIN_DIVIDE_BY_2 attribute to TRUE. This attribute divides the incoming
Description
Spartan-3A DSP FPGA Family: DC and Switching Characteristics
www.xilinx.com
F
F
CLKFX
CLKFX
< 150 MHz
> 150 MHz
Table 7
and
Device
Table
All
Min
0.2
–
–
–
36.
Min
15
-5
333
±300
±150
Speed Grade
Max
±1
-5
(5)
Speed Grade
Max
35
Min
0.2
–
–
–
Min
15
-4
-4
Table
333
±300
±150
Max
±1
Max
35
(5)
36.
Units
MHz
Units
ps
ps
ns
ps
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