I have downloaded the SPICE model for the Fully Differential ADC driver ADA4945-1 and have added the basic components as can be seen in the screenshots. However, the frequency response rolls off after 1MHz whereas the bandwidth in the datasheet mentioned is considerably higher. I tried changing the gains but the issue remains the same. I have attached the screenshots of the basic circuit along with the frequency response. The two curves are of the two differential outputs. Can someone please explain why the SPICE model is not behaving like the datasheet?
Couple of things:
1. You cannot run the ADA4945 off 20V supplies (+/-10V) as you have it configured. Change your supplies to +/-5V instead.
2. You have left the "Mode" tied to ground. You should either tie it V+ or V- depending on the operating mode you like.
See if the attached simulation file works for you?
ADA4945 LTspice simulation 8_8_19.zip
Thank you for pointing that out. Its working now