EEVblog #516 - LTSPICE Tutorial - DC Operating Point Analysis

[EEVblog]

Part 1 in a series of LTSPICE tutorial videos.
In this introduction Dave explains what LTSPICE is and how to do the simplest of the SPICE analysis options - basic DC operating point analysis.
Also how to draw basic schematics, display voltages and current on your schematic, and a beginner few traps to avoid.

[jancumps]

What do you use to make videos with screen capture and voice over?

[EEVblog]

What do you use to make videos with screen capture and voice over?

Camstudio
The trick is setting a fixed screen of 1280x720 so you don't get re-sizing distortion. Full HD is too big and ends up with text too small.

[floris]

I am very curious what you think of TINA
in the beginning of the 90's we used this in scool so this exits very long already
It has very nice analysis functions

[firewalker]

And LTSpice is available for Windows, GNU/Linux and MacOS.

Alexander.

[Dagon]

Good stuff, I was just starting to use ltspice so this is good timing!

There is indeed a lot of videos on ltspice out there already but a lot of them aren't very good.

[cyteen]

Any chance you could add the use of ASCO (A SPICE Circuit Optimizer) http://sourceforge.net/projects/asco/?source=pdlp with LTSPICE to your series of tutorials?

[firewalker]

Any chance you could add the use of ASCO (A SPICE Circuit Optimizer) http://sourceforge.net/projects/asco/?source=pdlp with LTSPICE to your series of tutorials?

I compiled a Win32 (didn't saw a Windows binary) version for him in case he wants to try it.

https://dl.dropboxusercontent.com/u/31742622/ASCO-0.4.9.rar

Alexander.

[EEVblog]

Any chance you could add the use of ASCO (A SPICE Circuit Optimizer) http://sourceforge.net/projects/asco/?source=pdlp with LTSPICE to your series of tutorials?

I have not used that before, but most likely not. It would be wise to stick with the stock install of LTSPICE for tutorials.

[Jebnor]

Fantastic! 

At the end, you were looking at the sample Audio Amp.  Any chance you could talk Doug into doing an Amplifer design tutorial series?

[mrflibble]

Nice tutorial, I think you covered the basics for operating point pretty well.  Including the ever popular M vs Meg. Have had fun with that one in the past, grrrrr.

[wblackledg]

excellent as usual dave!

So maybe this is a newbie question ,but for simple circuits can't you use this as a design tool and export it to create a pcb?

[nigel53]

Excellent stuff!

As said before loads of video's on this but most are not very good. I would tend to agree that concentrating on LTSpice is the better option than trying to cover other products as well. Looking forward to importing other models into LTSpice.

[Rigby]

Aah, thank you for this.  Just as I was beginning to play with LTSpice, too.  Excellent.  (I was going to type "Bloody Ripper" there but it just isn't cool when an American says it.)

Since you're going to teach us all how to use LTSpice, I think it would be extremely apropos if you (or someone) could start tossing up LTSpice schematics of the demo circuits you show us, such as the soft latch circuit and such, so that we can have a play as well.  Though, I guess if you're going to teach folks to use the tool, the students should implement the circuits in LTSpice themselves, huh?

Thanks again.

[mrflibble]

So maybe this is a newbie question ,but for simple circuits can't you use this as a design tool and export it to create a pcb?

Not sure if that's the easiest design flow around... In the past I have used gschem to do the schematic and then used that in ltspice. All in all, I don't think ltspice is the obvious choice for schematic capture (with the goal of producing a pcb from the schematic). Ltspice is however a very nice choice as simulation engine.

[Zbig]

I admit I haven't installed it yet but is there any simple way of switching it to "European" schematic symbols (I don't know the proper name of the standard)? You know, rectangles for resistors instead of the springy-thingy, etc. It's not an "ideological" thing for me or anything, it's just easier for me to wrap my head around when seeing more familiar visual language (e.g. when I see "US" resistor symbol, I immediately think "inductor").

[Bored@Work]

is there any simple way of switching it to "European" schematic symbols

Yes and no. It comes with a few European symbols. But you would normally have to select them separately (from the component menu, not from the toolbar), which gets annoying pretty fast.

Alternatively, what you can do is to replace the US symbols in the LTspice installation with the European ones. This is relatively simple, because LTspice uses one file per symbol. You will find that a few European symbol versions are missing, so you need to draw your own with LTspice's symbol editor. And be aware that an LTspice update "sync release" undoes your changes.  It is important that you keep the relative position of all the pins of all the symbols you replace.

I have a .bat script that I run as administrator which replaces a few symbols with my own ones, including European symbols. It just does a simple copy of the contents of my symbol directory hierarchy to the lib\sym directory hierarchy of the LTspice installation.

[hikariuk]

I admit I haven't installed it yet but is there any simple way of switching it to "European" schematic symbols (I don't know the proper name of the standard)? You know, rectangles for resistors instead of the springy-thingy, etc. It's not an "ideological" thing for me or anything, it's just easier for me to wrap my head around when seeing more familiar visual language (e.g. when I see "US" resistor symbol, I immediately think "inductor").

I believe the standard for European style symbols is IEC 60617.

[wblackledg]

I was trying to emulate this with  ltspice as a tutorial for myself.  I have an interest in Crystal radios.

I couldn't figure out the switch or the antenna?  perhaps this is not a very good example of a first try?

thanks.

[c4757p]

For the antenna, use a voltage source with the impedance of the antenna as series resistance. Obviously you'll need to know the signal strength. For the switch, just make a connection where you want the switch closed.

Good luck finding a working model of a germanium diode.

[wblackledg]

For the antenna, use a voltage source with the impedance of the antenna as series resistance. Obviously you'll need to know the signal strength. For the switch, just make a connection where you want the switch closed.

Good luck finding a working model of a germanium diode.

yeah, I think that diode is sort of the heart of any crystal set.  that was why I was wondering if this was not the best place to start.. 

[c4757p]

Anyway, you haven't put your home country in your profile, so I don't know whether advising you on how to simulate a crystal radio in SPICE would be considered aiding and abetting criminal blasphemy.

[Zbig]

Alternatively, what you can do is to replace the US symbols in the LTspice installation with the European ones. This is relatively simple, because LTspice uses one file per symbol. You will find that a few European symbol versions are missing, so you need to draw your own with LTspice's symbol editor. And be aware that an LTspice update "sync release" undoes your changes.  It is important that you keep the relative position of all the pins of all the symbols you replace.

I have a .bat script that I run as administrator which replaces a few symbols with my own ones, including European symbols. It just does a simple copy of the contents of my symbol directory hierarchy to the lib\sym directory hierarchy of the LTspice installation.

Thank you, that's a helpful hint and I'll definitely try it out.

[alanb]

I have recently started to use both Ltspice and Diptrace and have tried unsuccessfully to transfer net lists from Diptrace to LTSpice? When exporting from Diptrace I get the error 'Spice settings are not defined for the following parts......' followed by a list of all the components.
Am I missing something or does this not work?

[DutchGert]

Very nice one Dave, please keep it up!

Perhaps U could link in the LTSpice schematics u made/use so we can play along at home?