Fully Diff has the 150ohm so I am drawn to use pseudo diff since it has the 75ohm and my camera is 75ohm full diff.

What is the proper logic strategy to use for selecting the circuit below?

Glenn

Fully Diff has the 150ohm so I am drawn to use pseudo diff since it has the 75ohm and my camera is 75ohm full diff.

What is the proper logic strategy to use for selecting the circuit below?

Glenn

- 1 person found this helpful
Hello,

For a fully differential signal I would assume that you would have the setup above;

- The camera output is twice the amplitude of a pseudo-differential CVBS signal.
- The camera has 75 Ohm series termination on both outputs.
- A CVBS cable with an impedance of 75 Ohm per length is used.
- The fully differential signal is terminated using the recommended input network to the ADV728x.

In this setup Resistor R1 provides the RF end termination for the fully differential CVBS input line. The camera sees 150 Ohm differential impedance so R1 needs to be set to 150 Ohms in order to prevent an impedance discontinuity.Therefore we recommended that the resistor R1 should be 150 Ω for fully differential CVBS.If the camera you are using sees a different differential impedance then set R1 to match this accordingly.I hope that this clears up any confusion.Regards,Robert HinchyApplications Engineer,Analog Devices Inc.

Hello,

For a fully differential signal I would assume that you would have the setup above;