System Modeling Blog

Lately I’ve been working with customers interested in using SystemVision to simulate either a real production design, or some sort of evaluation test circuit. To a customer, however, each ran into the “don’t have a simulation model” challenge for one or more devices in their system. Despite SystemVision’s large VHDL-AMS and SPICE model libraries, we didn’t have a … Read More

Mixed-Signal, analog modeling

In Part 5 of this series we used the mathematical descriptions of the thermal and electrical properties of an incandescent lamp to create the architecture of a VHDL-AMS-based simulation model. Now it’s time to finish the model, and this blog series, by creating a VHDL-AMS entity for the lamp model. As I mentioned in Part 5, the VHDL-AMS entity defines how a model connects to other elements in a system, … Read More

HDL, Modeling, analog modeling

If you’ve followed this Analog Modeling series, you know we’ve been talking about a general process for HDL-based modeling of analog behavior. If you’re new to the discussion, or simply want to review what we’ve talked about so far, check these links: Part 1, Part 2, Part 3, Part 4. In my last post we developed a set of equations describing the relationship between the thermal … Read More

HDL, analog modeling, Modeling

It’s time to dig a little deeper into the incandescent lamp behavior I introduced in Part 3 of this blog series. My goal is to select a set of equations that best describe the elements of the lamp’s behavior that I want to quantify during simulation. Recall my comment in Part 3 that a lamp has several characteristics worth analyzing including electrical properties, thermal properties, aging … Read More

vhdl-ams training, HDL, analog modeling, Modeling

Welcome to the third installment in my Analog Modeling blog series. In Part 1 I wrote about why equations are important for simulation. In Part 2 I suggested a process flow for turning device equations into a simulation model, and introduced the basic structure of a VHDL-AMS model. Now it’s time to begin the model definition process. As I outlined in Part 2, the first step is deciding what you want … Read More

HDL, analog modeling, Modeling

In Analog Modeling – Part 1 I reviewed the importance of equation selection in the analog modeling process. In a nutshell, the first step in getting good simulation results is choosing equations that best describe the behavior or device you want to analyze. Your analog equation set could be as simple as a single transfer function describing the relationship between the inputs and outputs of a … Read More

HDL, Modeling, analog modeling

I recently spent some time rummaging around my basement. I suppose my basement is not unlike many others — it’s kind of my family’s catch-all storage place for items too big to fit in a closet. Besides housing my HVAC and water heating systems, my basement is home to a variety of holiday decorations, lots of canned, bottled, and bulk food items, a small collection of mismatched folding tables … Read More

Modeling, analog modeling