Version 1.0
Page 32 of 44
SMT370v2 User Manual
F
Synthesized
= (M/N)
MHz -
With 500 < M < 250 (binary encoding) and N can take one of
the following values: 1, 1.5, 2, 3, 4, 6, 8 or 12 (for respectively “000”… ”111”
encoding). See
datasheet for more information performance, jitter, etc.
The following diagram shows how clock signals can be routed on the board.
A and B
Xilinx
FPGA
Virtex-II, FG456
XC2V1000-6
324 I/O Pins
1.5V Core
3.3V I/O
#1
AC or DC
coupling
2xAD6645 ADCs
14-bit @ 105MSPS
52-pin LQFP
30 I/O pins; 28-bit data; ctl
1x AD9777 DAC
16-bit @ 400MSPS
80-pin TQFP
44 I/O pins; 16-bit data; ctl
#4
#3
RF
transformer
#2
Clock feedbacks
Clock feedback
Clk
1
opamp
opamp
Clock synthe-
sizer ADCs
Clk
2
AC or DC
coupling
RF
transformer
ADC A
ADC B
Clock synthe-
sizer DAC
Bit27
0
1
Bit26
0
1
0
1
0
1
Bit25
Bit24
Figure 10 - Clock Routing.