Needs in the worldwide competition push teams to master more and more their design flow in order to minimize risks, costs, time to market, and potential liabilities. The classical V shaped design cycle is full of limitations. With new HDLs and their intrinsic qualities many design flow like top-down, bottom-up or meet-in-the-middle has been proposed. These proposals are far away from actual industrial needs. This paper proposes a new design flow with reinforcing the V-cycle with modelling and simulation at each step in order to produce a virtual prototype. We will show all the assets of the “Functional Virtual Prototyping Cycle”. We will show that VHDL-AMS is a very good candidate to lead this task. We set up this design flow on a Parallel Optical Module from Thales. This solid state module, without heat sink, includes different components, including VCSEL and photodiode arrays, optical fibbers and electronics implying electrical, optical, mechanical and thermal interactions, intr...