Hi,

The syntax to output individual node voltages with respect to ground as a .wav file is:
.wave <filename.wav> <Nbits> <SampleRate> V(out) [V(out2) ...]

With this syntax I can only output individual node voltages with respect to ground. I would like to know how I can output the voltage "between two nodes". For example the voltage between node a and node b.

Thanks in advance for your help.

 

Hi,

The syntax to output individual node voltages with respect to ground as a .wav file is:
.wave <filename.wav> <Nbits> <SampleRate> V(out) [V(out2) ...]

With this syntax I can only output individual node voltages with respect to ground. I would like to know how I can output the voltage "between two nodes". For example the voltage between node a and node b.

Thanks in advance for your help.

Create a behavioral voltage or current source that represents the voltage difference between the two nodes. Like this:

 

Excellent!
Thank you so much for your help.
I would also like to know if we can achieve this without extra circutry. I mean obtaining the same effect with an appropriate syntax.

 

Excellent!
Thank you so much for your help.
I would also like to know if we can achieve this without extra circutry. I mean obtaining the same effect with an appropriate syntax.

As far as I know the .wave command does not allow expressions, only node names. I think there may be reasons why this is the case relating to saving node data as it is calculated but not being able to compute random waveform expressions in the middle of matrix operations. this is just rank speculation so take it with a grain of salt.

 

What I did was to use a voltage differential amplifier or voltage subtractor opamp circuit and connect the nodes to the inputs of the circuit and use the output voltage. Your solution eliminates the need for this.

 

Excellent!
Thank you so much for your help.
I would also like to know if we can achieve this without extra circutry. I mean obtaining the same effect with an appropriate syntax.

This uses an alternate node syntax

 

Great!
Thanks a lot.

 

Or you can use the E source, voltage dependent voltage source, just put 1 to have unity gain,instead of the predefinded E.

 

I will check this. Thanks.

 

hi Ozgur,
Just tried it, works fine.
E

 

You can also use the operators from the LTspice Control Library. Like this:

 

I just installed the LTspice Control Library and I will have a look. Thanks.