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While on a long drive, I like to sing along; say Eye of the Tiger or Johny B Goode or Sweet Home Alabama (even though I don’t live in Alabama), the music being an active part of the journey, especially when I am just beginning the drive, fresh and eager, looking forward to the trekking and wildlife sightings. Compare this with the schematic design phase. Whistling and nodding while placing the parts: here’s the library and there’s the part.
But sometimes, I just want to listen, say a pipa-based Chinese song or classical music, Eastern or Western, or a charming piece of Jazz; when, for instance, others are napping, or each is lost in his or her own thoughts, staring outside blankly. In the design world, it is that phase where you are intently staring at the design, connecting the grounds and power, contemplating any falls through the cracks, or ruminating on what was missed and what might be missed.
And then, sometimes I want the music to be passive, I am not even aware it is there, a trance track, for instance; at night or while negotiating a difficult stretch or crawling through bumper to bumper traffic. Of course, if I am driving through a wood (and that's what I do quite often), I want to hear the music of the forest; cicadas, the wind, birds, and frogs on a rainy day. Is not this the same wishful design phase where you run the simulation and wait, hoping all goes well; the circuit does not smoke or the Monte Carlo Analysis result is more certain than uncertain and the yield is as expected.
But very often, as in my drives or design cycles, I am jolted up. Probably, the road map app I used was not up to it in the wild or the weather played havoc or, delightfully for me, a deer just crossed the road. As for my designs, most probably, I used a part that cannot be simulated. The part does not have an associated model. And, that’s quite a jolt if you’re in a hurry and there’s a deadline looming.
But worry not. In the design world, at least, you can download and associate a model in the go (pun intended). Thank the Internet for the convenience, freedom, and ease that it gives: search what you want, buy, and download. And, as the title of this write-up says, it’s “simulation for a song” – the process is simple and inexpensive with the added benefit of freedom to choose.
Now, when you install a schematic editor and a simulator, say PSpice Mixed Signal Simulator, the most commonly used models are installed as libraries, the .lib files in the library directory. So, you can open Capture and start designing and simulating immediately. It is as easy as that. But what if you are designing something not so ‘common’, say, a Permanent Magnet Synchronous Motor Drive for the automotive industry or a monitoring device for IoT applications?
That’s why I love the new and simplified Associate PSpice Model interface of PSpice. I search for a model, download it from the Web, and associate with the part in my design. Or, I create a new symbol on the fly, while associating a PSpice model using Symbol Editor.
Now that I think of it, it is easier than me collecting music for my long drives. You just right-click a part in your design in Capture and choose Associate PSpice Model, browse to the downloaded library, select the model, and map the symbol pins with the model terminals.
And, while I get ready for my next drive; I hope, next time you come across a part without an associated model you face it with a knowing smile and a right-click.