Hi, I put together the simple differential receiver model. I used Mike's case last week as an example. It is a very simple case, but it helps to go through the whole process yourself. This simulates OK with Spectre. Note that it calls "subset_IBIS_macro_library.va"; I only put in there what this module calls for. Ken Willis Cadence Design Systems 270 Billerica Road Chelmsford, MA 01824 (978) 262-6540 <<simple_100_ohm_diff_rcvr.va>>