Post Go back to editing

AD9695 SYSREF DC COUPLED LVPECL TERMINATION

Thread Summary

The user is driving a SYSREF signal to the AD9695 from the HMC7044 using a 1-shot DC-coupled LVPECL configuration. The recommended termination network converts the LVPECL signal to LVDS levels, with Vcc = 3.3V. For 16 ADCs, the resistors should be placed close to the receiver side, and using 1.8V DRVDD is not recommended due to the driver's output voltage of around 2.1V.
AI Generated Content

Hi

I'm driving sysref to AD9695 from HMC7044.

Since I use 1shot sysref it must be DC coupled. HMC can't work in LVDS mode for DC coupled 1shot sysref (known issue) thus forces me to work in LVPECL.

from HMC (driver) point of view, recommended termination is:

with DC parameters:

On the other hand, AD9695 requirements are:

So it seems that Vcm is at the edge of the upper value , and also swing.

How do you reccomend to connect?

Parents Reply Children
No Data