W2375EP Power Electronics Library Element

The trend in high performance switched-mode power supplies (SMPSs) is towards faster switching speed – high di/dt in the industry jargon. But there’s a challenge. Traditional workflows don’t work in the high di/dt era because they are blind to the spike voltages induced across layout parasitics, V_spike = L_parasitic * di/dt. Thus, in the high di/dt era, it is necessary to add a post-layout analysis step to the workflow, in between pre-layout circuit simulation and physical prototyping steps.

To do this you first build up the pre-layout circuit simulation from both general-purpose Advanced Design System (ADS) lumped element components and special-purpose components from this Library. Then you use ADS Momentum field solver to extract layout parasitics into an EM-based model that you can “back annotate” on to the pre-layout schematic and re-simulate. In this way, the spike voltages can be determined, and (using “What if…” design space exploration) reduced to an acceptable level before sending the design for fabrication. This “virtual prototype” method gives you insights from our advanced data displays and saves you expensive, time-consuming, non-deterministic board spins. In addition and unlike a lab “smoke test”, there are no destructive failures in a simulation! Save those precious power devices for a prototype design that post-layout simulation has given you confidence in.

To support this flow, the ADS W2375EP Power Electronics Library contains components specifically built for Power Electronics including components for closed loop feedback regulation of SMPSs. For example, the Pulse Width Modulator works with both the Transient Convolution and Harmonic Balance simulators. The component palette also provides easy access to ADS built-in component that are often used in power electronics.

Descriptions of each of the components are summarized in the table below.