Best Circuit Sim (Free only)

[random person]

I would say without a doubt, Circuit Simulator Applet is the most amazing thing ever! .... Its a java ap so no "download" required. All simulations are live. At work we got orcad( non free version of pspice) .. which is very slow in comparison but I know its required for professional IC based circuits... (but there are rarely sim files for commercial ICs).

Annyyhooowww great simulator and can be used for nice quick drawings.

 

[laserpyro]

I remember in school we used one called crocodile clip.
Not sure if it'll be any good for your purposes.

 

[RayBurne]

The JAVA Falstad simulator can be downloaded onto a net book and used totally in off-line mode. Most useful and fun. I recently published in another thread the import code for a laserdiode dummyload just for grins... click the switch to select between Red or Blue diode, play with battery voltage and observe diode current.

-Ray

 

[Bionic-Badger]

I don't like using Java-based apps and have outright disabled it from my browser. Plus I like being able to save designs out and such. Some of the chip manufacturers have their own analog simulators that you can download and use for free. For example:

TINA-TI - Texas Instruments - Note that it says "order now" but it is actually free.

LTSpice IV - Linear Technologies

Here's an open source one called NGSpice:

NGSpice - GNU spice simulator.

Finally NL5 can be used in demo mode, which limits you to 20 devices. Some people prefer it over the above despite its limitations:

NL5 Circuit Simulator

 

[random person]

I don't like using Java-based apps and have outright disabled it from my browser. Plus I like being able to save designs out and such. Some of the chip manufacturers have their own analog simulators that you can download and use for free. For example:

TINA-TI - Texas Instruments - Note that it says "order now" but it is actually free.

LTSpice IV - Linear Technologies

Here's an open source one called NGSpice:

NGSpice - GNU spice simulator.

Finally NL5 can be used in demo mode, which limits you to 20 devices. Some people prefer it over the above despite its limitations:

NL5 Circuit Simulator

LT spice is certainly decent... my fav of the ones listed. However... problem with these is the lack of models outside the company offering them.