It was a few years ago that I first heard of a free site where you could draw and simulate designs. “What’s the point?” I thought. But, the idea is taking off. Was I wrong?
I questioned the usefulness of this cloud concept because there had already long existed good, free circuit simulators. A quick download, and off you go, drawing and simulating. Why deal with the extra vagaries of service-provider availability, and of course, Internet access?
Well, as with any other cloud-based service, there are advantages, such as being able to work anywhere, on any supported device, and not having to deal with the software directly. And while the services out there now seem mostly suited to exploration, hobby, and simple prototype use, they will keep getting better. Some are arguably already professional grade.
To start, I’d be remiss not to mention an early, limited implementation of the online design and sim concept. For years, National Semiconductor (now TI) has offered Webench as a quick way to create designs using their parts. Switching converters are the focus, but the tools also handle circuit blocks like filters and clock trees.
Back to the newer services, that system I first encountered a few years ago was CircuitLab. It can handle schematic entry and simulation, and there’s integration with Jameco for ordering parts. Here’s a look at the edit screen:
Distributor Digikey has jumped into the fray with Scheme-it. The system does schematic capture, not simulation. Of course, it has a tight connection to Digikey’s massive parts selection. Reference designs from a few companies are also available for immediate use.
For More Details: Design & simulate in the clouds
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