I am working on PCIe 3.0 compliance testing from signal integrity and power integrity point of view. I would like to understand the difference between IBIS and IBIS-AMI model and which model is good for my simulation? These models are used in transient and channel simulation of PCIe 3.0.
The IBIS file is the representation of the analog section of the chip which generally include I-V & V-T look-up tables. IBIS files are behavioral models of individual analog buffers. As the chip designs became more and more complex, more DSP techniques were needed to maintain an open eye at the receiver data slicer. While the IBIS Open Forum worked with the industry to amend the IBIS standard to incorporate changes, analog IBIS buffer models could no longer keep up with the DSP design. Vendors were again providing their own encrypted models which were platform specific. Thus the IBIS community worked to extend the IBIS models and IBIS-AMI models were born. AMI stands for Algorithmic Modeling Interface and as the name indicates, it is designed to handle modeling of the algorithmic functions of an I/O, namely the DSP. IBIS-AMI models provide the end user with the model portability that they need while ensuring the vendors that their IP is protected. The user settable parameters for equalization are generally included in the AMI file.