{"id":69,"date":"2013-01-10T01:47:46","date_gmt":"2013-01-10T09:47:46","guid":{"rendered":"https:\/\/www.falatic.com\/?p=69"},"modified":"2016-08-25T03:27:04","modified_gmt":"2016-08-25T10:27:04","slug":"memristor-simulation-with-ltspice-a-practical-example","status":"publish","type":"post","link":"https:\/\/www.falatic.com\/index.php\/69\/memristor-simulation-with-ltspice-a-practical-example","title":{"rendered":"Memristor simulation with LTspice – a practical example!"},"content":{"rendered":"

Update 2016-08-25: <\/strong>LTSpice XVII is out! It doesn’t look that different from IV but it’s definitely improved under the hood. There is a quirk though:\u00a0it installs a set of component libraries in the usual place, but also in\u00a0C:\\Users\\%username%\\Documents\\LTspiceXVII\\lib\u00a0<\/em>… and it ONLY uses that second set! (As a test, I removed the examples and libs\u00a0in the install dir and it\u00a0worked just as well.) This may be a transient bug or part of the migration to a new directory model – either way, if the normal install doesn’t work for you,\u00a0install the memristor library to the folders in\u00a0C:\\Users\\%username%\\Documents\\LTspiceXVII\\lib<\/em><\/strong><\/p>\n

Update 2016-02-08:<\/strong> The examples can be found on my GitHub repo (MartyMacGyver\/memristor-modeling)<\/a><\/strong><\/p>\n

Update 2015-03-30:<\/strong> My goal was to create\u00a0a simulation in LTspice using a memristor component… I did NOT write the SPICE model for the memristor component itself (it’s\u00a0straight out of the paper by Biolek, Biolek, and Biolkova<\/a>\u00a0as noted in the Readme file).\u00a0Due to the limitations of that model, this\u00a0simulation only works in transient\u00a0analysis<\/strong> mode.\u00a0The parameters are\u00a0“.tran 0 3s 0 3m uic<\/em>” (uic<\/em>\u00a0used to be called\u00a0skipbp<\/em>).<\/p>\n

\n

Lately I’ve been getting back into the EE groove with some random electronics projects (such as an Arduino-based LED strip driver<\/a>). I’ve also been dabbling with different circuit simulators like Micro-Cap (which I used back in college but which is VERY expensive for the regular version… still, it’s handy for quick little sims to learn new things, especially in the digital realm).<\/p>\n

\"Memristors<\/a><\/p>\n

Today I stumbled on\u00a0LTspice from Linear Technology<\/a>, which I found to be surprisingly intuitive (and given that it’s based on the venerable and powerful SPICE<\/a> it’s that much more worth learning). It’s not as animation-friendly as Micro-Cap but it’s pretty easy to make custom components (and where else can you simulate the actual inner workings<\/em> of a 555 timer<\/a> or a 741 op-amp<\/a>?) (And yes, the 741 is not something you’d reach for normally nowadays, but they are instructive nonetheless.)<\/p>\n

Memristors have intrigued me since they made the news a few years back, when discoveries were made of practical memristive materials. You can read more about them on Wikipedia<\/a> and so on, and though very subject is not without controversy I personally think they will prove to be a valuable technology going forward. I found them intriguing from both the EE and the MSE perspectives.<\/p>\n

Side-note: if you find yourself wondering more about why a device does what it does (in my case, the humble MOSFET) than regurgitating Kirchoff’s Law and applying Th\u00e9venin’s theorem, you’re probably better off in Materials Science Engineering than Electrical Engineering. At least that’s what happened to me… that and a very grumpy EE prof who made it clear we’d all be obsolete, unemployed and grumpy like him soon anyway. And you can always fall back on CS when the semiconductor market tanks…<\/p>\n

Given all that, today I decided to see if I could simulate a circuit with a memristor in it. Problem is, while some sims have memristors, LTspice does not, and apparently nobody out there has published a simple example that actually works (I found videos – who writes a text tutorial in a video? – and a broken webpage, but I never found a working sim). So, I made one… and after a few false starts I got it to work. Not bad for an evening at home!<\/p>\n

To try out my demo LTspice-based\u00a0memristor simulation, please visit my GitHub repo (MartyMacGyver\/memristor-modeling)<\/a>\u00a0and follow the instructions there for how to install and use it.<\/p>\n

And to reiterate, this is a demo based on the SPICE model of a memristor as described in one paper… this is for educational purposes only and no, I can’t help you with your homework. \ud83d\ude00<\/p>\n

To test all this, install the latest LTspice, install the files per the Readme,\u00a0load up\u00a0memristor_sim.asc, and run the simulation. This currently works\u00a0with LTspice IV\u00a0and the latest\u00a0LTspice XVII.<\/p>\n

 <\/p>\n\n","protected":false},"excerpt":{"rendered":"

Update 2016-08-25: LTSpice XVII is out! It doesn’t look that different from IV but it’s definitely improved under the hood. There is a quirk though:\u00a0it installs a set of component […]<\/a><\/p>\n","protected":false},"author":1,"featured_media":158,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"Layout":"","footnotes":"","_links_to":"","_links_to_target":""},"categories":[85,108,86],"tags":[124,122,121,123],"class_list":["entry","author-marty","post-69","post","type-post","status-publish","format-standard","has-post-thumbnail","category-electronics","category-science","category-software-and-hardware-development","tag-electronics","tag-ltspice","tag-memristor","tag-spice"],"_links":{"self":[{"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/posts\/69","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/comments?post=69"}],"version-history":[{"count":0,"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/posts\/69\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/media\/158"}],"wp:attachment":[{"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/media?parent=69"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/categories?post=69"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.falatic.com\/index.php\/wp-json\/wp\/v2\/tags?post=69"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}