SPICE = Circuit Simulator...
 

I was over at the house of an engineer friend of mine recently. He was helping me with a technical issue, specifically verifying if a stepper motor driver that I had purchased actually worked, and if it's performance could be improved.

We were easily able to verify that it worked, but then came the surprise to me...

When we were working on possible ways to improve the driver, he opened up a computer program that already had the schematic of the circuit in it. I had already sent him the schematic, and he had already entered it into the program.

What was surprising was that the program was able to simulate the performance of my stepper motor driver. It allowed us to quickly and safely try various changes to key components, and we were able to see what the results of those changes would be as if we were looking at an actual circuit with an actual oscilloscope. It was a total revelation!



SPICE has been around for a long time, in various flavors, but this one (LTspice IV) is very fast and 'gooey' (good graphical user interface).

Even better, the program is freely available, without time or capability restrictions right HERE.

There is also a video of how LTspice IV works right HERE. Also, a Getting Started Guide is available HERE.

An appropriate search will yield videos of it's use on YouTube.

I really wish I had access to something like this a long time ago, because it would have deepened my understanding of how basic circuits work.

Why is it free? The company that offers this program, Linear Technology, knows that SPICE is a favorite tool in the field of electronic design, so they created a fast and excellent version of SPICE and included an extensive library of their products, which just happen to be well regarded. This makes development of circuits using their components very easy and very fast. But it is possible to add to that library, other components with the appropriate performance parameters.

It's also possible to enter your own schematic and the values of the components, and the program will quickly build a simulation of that circuit.

Simply amazing...


Best,

-AC_Hacker

That is cool. I used a similar web based program when taking a (free) online course through MIT on an intro to electronics. They are very useful.

In case anyone is interested, here is the link. They offer many classes: MIT OpenCourseWare | Free Online Course Materials

Double Plus Good!

-AC

Good to hear you have it working.

Orcad used to have free 'student' version of PSpice.

The student and LT type of spice programs are good for relatively simple stuff.

Once you get into areas of subltle design failures, the full programs are quite something nowadays. Everything from transformer core losses and flux levels to eye charts of digital transmission lines. (but full versions pricey) Have used PSpice since about 1988, you originally had to hand write a netlist, no schematic tools. Great for transient analysis.

How deeply have you looked into the features of LTSpice IV?

There may be more there to be found...

-AC

How deeply have you looked into the features of LTSpice IV?

Not nearly as deeply as I will once I fully retire and no longer have access to the corporate license of the $10K program I use now <G>