Agilent Technologies 81250, Installation Manual

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Installing ParBERT 43/45G Systems 7 Special ParBERT Systems
Agilent 81250 ParBERT Installation Guide, May 2004 7-11
To keep the high-frequency cables as short as possible, the working height
for placing the DUT should be established between the middle and the
bottom frame.
Making Clock Connections
The MUX module requires a clock signal. It has to be synchronized with
the generator frontends.
The DEMUX module has a built-in clock data recovery (CDR) circuit that
allows to recover the clock from the incoming data. But the DEMUX
module can also be controlled by an external clock.
Both modules have clock input and output connectors. With ParBERT
43/45G, there are many ways for generating and connecting clock pulses.
Using the Built-in Clock Module
The simplest clock source is the E4808A clock module. Its use is
illustrated in the figure below.
16
/
Divide
PLL
43.2G Pattern
Generator Bundle
38 .. 43.2 Gb/s
593.75 .. 675 MHz (MCLK)
Internally or
externally:
9.5 .. 10.8 GHz,
or any subrate
:n, n = 1…255
Subrate clk out:
19.5 .. 21.6 GHz,
9.5 .. 10.8 GHz,
2.375 ..2.7 / 593.75 .. 675 MHz
Figure 68 Using the Built-in Clock Module