Guys,

I am working on series of lessons on LTspice which could be extremely useful if you want to learn LTspice or get deeper into to some advanced level simulation. First lesson is up on my blog, check it out. I am open for any feedback and if you would like to see your favorite circuit simulated, please let me know.

Here is the excerpt and and a link to full post:

https://iexploresiliconvalley.com/2019/02/03/ltspice-lesson-1-generating-iv-curves/LTspice Lesson 1: Generating IV curves

Posted on February 3, 2019 by iexploresiliconvalley

“Never perform a measurement or simulation without first anticipating the results you expect to see.” ~Eric Bogatin’s Rule # 9

Learn these spice commands: .dc .param

In these 10 lesson series, we will explore LTspice circuit simulator. Assumption is that you’re a beginner or someone who already plays around with it a bit and feel it has potential to solve circuit problems, and perhaps provide intuition and insight how electronic circuits works. Ultimately, it will help solve a real world EE problem and continue to provide a quick go to tool for a quick circuit simulation of some proof of concept.

The approach we will take is that we will never simulate a circuit unless we know what output we expect to see. This is beautifully captured by world-renowned signal integrity expert Eric Bogatin rule # 9. [1]

First of all, why start with IV curves? Voltage-Currrent (aka IV) relationship of a component can tell us a lot about behavior of that component. In a nutshell, by applying a voltage across its terminal and measuring the resulted current, one can figure out the resistance or more generally impedance of the component. Later this knowledge can lead to electrical models which can help design and predict the behavior of a circuit. This is a good starting point as we will get to know immediately two of most important LTspice simulation commands: .dc and .param

We will look at IV curves of following components:

Resistor

Diode

NPN and PNP BJT

NMOS and PMOS MOSFET

Solar cell

We will be using following 5 steps approach for each of the circuit in these tutorials:

Step 1: Draw a circuit.

Step 2: Add proper dot simulation command.

Step 3. Predict its behavior.

Step 4: Simulate and verify behavior with your prediction.

Step 5: (Optional) Repeat step 3 if result doesn’t match prediction and extend the example for some other use case or different parameters.

https://iexploresiliconvalley.com/2019/02/03/ltspice-lesson-1-generating-iv-curves/