User`s manual

X5-GSPS XMC Module
The external clock input at connector J4 is AC coupled and can accept either sine wave or digital clock sources. The
following table gives the electrical requirements for the clock input.
Feature Description
Input Impedance 50 ohm
Input Coupling AC
Input Connector SMA
Minimum Input Swing 200mVp-p (-20.8 dBm)
Maximum Input Swing 2.0Vp-p (-0.8 dBm)
Maximum Frequency Supports converter maximum clock rates (1.5 GHz)
Jitter <0.5 ps, pk-pk
Figure 22. Input Clock Electrical Specifications
Oscillators may be installed at location Y5 to provide an on-board clock source for applications which can run at a fixed rate
and do not require or cannot support external clock sources. Oscillator electrical specifications are given below.
Feature Description
Power Supply 3.3V
Output I/O Standard LVPECL
Package 5mm x 7mm, surface mount, 6 pin
Figure 23. Clock Oscillator Electrical Specifications
A 100 MHz oscillator is standard for Y5. Compatible oscillators include Pletronics LV9945DEVand Raltron C9P. As
always, oscillators should be carefully evaluated for their phase noise performance in order to ensure the best signal integrity
from A/D data. A oscillator with < 500 fs jitter is recommended.
Triggering
The X5-GSPS has a trigger control component in the FPGA that controls the data acquisition process. The sample clock
specifies the instant in time when data is sampled, whereas triggering specifies when data is kept. This allows the application
to collect data at the desired rate, and keep only the data that is required.
X5-GSPS User's Manual 81