DAC38J84: DC-COUPLED SYSREF

Hi,

In the DAC3xJ8x Device Initialization and SYSREF Configuration application note page 19 there is an explanation how to work in LCPECL DC Coupled configuration:

In addition, in DAC38J84 EVB sch the following network is described:

• why is the network not the same in both cases?
• The purpose of the network is to down  The common mode from 2 V is to 0.5 V through resistor divider, but the resistor divider is 1:2, isn't it?
• what is the signal Vpp amplitude in the DAC entrance? is it strong enough?

Thanks,

Asaf