Sundance SMT784 v.1.0 User Manual
Page 14

Version 1.0
Page 14 of 31
SMT784 User Manual
Clock Distribution
There is one integrated clock generator on the mezzanine module (AD9510 – Analog
Devices). The user can either use this clock (on-board) or provide the module with an
external clock (input via MMCX connector).
ADCs can all receive the same clock or the integer multiple of it (x2, x3……x32), the
maximum being 125MHz for each ADC. This clock can be coming from the on-board
VCXO or from an external source.
An extra connector outputs the reference clock for multiple-module systems.
Figure 4 Clock Distribution
The main characteristics of the mezzanine clocks are as follows:
External Reference Input
Input Voltage Level
0.5 – 3.3 Volts peak-to-peak (AC-coupled)
Input Impedance
50-Ohm (Termination implemented at the connector)
Frequency Range
0 – 100 MHz.
External Reference Output
Output Voltage Level
1.6 Volts peak-to-peak (AC-coupled)
Output Impedance
50-Ohm (Termination implemented at the connector)
External Sampling Clock Input
Input Voltage Level
0.5 – 3.3 Volts peak-to-peak (AC-coupled)
Format
Single-ended or differential on option (3.3V LVPECL).
Frequency range
10-125 MHz