ADA4945 SPICE Model freq response not similar to the one in datasheet

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?

Parents Reply
  • Hi Hooman,

    When I use your LTSpice simulation (with no changes) I get a good frequency response on the P output (-3dB @ >100MHz) but a poor one on the N output. (-3dB @ 27MHz)

    This also occurs if I update to the latest V1.1 spice model of the ADA4945-1.

    What am I doing wrong, or is this a true representation of the device?

    I am looking for a single ended to differential driver that is flat to 50MHz (preferably with the +ve and -ve clamp feature)