Fully differential op-amp model on candence

[geo24]

Hi all,

I am trying to build a simple fully differential op-amp just use VCCS.

Here is the single-ended design I do in the cadence.

So I am wondering how can I build a fully differential op-amp model.
I don't need transistor level design. I need a model so I can change gain, bandwith. It's for my project. So I wanna have higher level design use ideal models before I replace them with transistor level designs.

If you have any other suggestion, please feel free to let me know. Thanks.

 

[AMS012]

Dont connect the bottom node to ground, instead bring it out as Vout-, name Vo as Vout+. This should give you a fully differential design. Break the Ro and connect its middle point to a voltage source (VoutCM) to define the output common mode voltage.