How to get circuit results outputted from LTsice?

[Flyback]

Hi,
I wish to run LTspice simulations, and then automatically get an output from them which is eg the power dissipated in the mosfet in watts.
Eg in the attached simulation, “V(N007,N009)*Id(M1)+V(N006,N009)*Ig(M1)” is the mosfet power in watts, how do I get the simulator to automatically spit this number out after the sim is run?

 

[alec_t]

Run the sim, plot the data of interest, left-click in the plot pane, then under the File menu select 'Export data as text'. A pop-up allows choice of data to export.
You can then enter the saved data into a spreadsheet.
Alternatively, you can use the .WAVE command to save node data as a .wav file (but data gets scaled down to a peak amplitude of 1).

 

[Flyback]

Thanks, sorry i didnt see it...eg in the attached, how do i get it to output the result of the exression...
V(N016)*I(R1) + V(N017)*I(R2)

 

[ronsimpson]

11.5 watts.
I hold down the ALT key and put the cursor on the part in question. Then click. At adds trace to the graph that shows 11.5 watts.

 

[Flyback]

Thanks yes, i appreciate that, the thing is i have another simulation where i need the sum of the power in 5 different fets, and i need a quick way of getting that number out of the simulator....without ALT clicking each fet and adding them all up.

 

[alec_t]

Use a behavioural voltage source B with the function V=(V(N016)*I(R1) + V(N017)*I(R2) ) + ..........) and plot the output of B, then export as text if you want.

 

[eTech]

Thanks yes, i appreciate that, the thing is i have another simulation where i need the sum of the power in 5 different fets, and i need a quick way of getting that number out of the simulator....without ALT clicking each fet and adding them all up.

Use the “.meas” directive with the appropriate equation. You can then view the results in the error log. You can also use “AKA” and step to perform a simulation on multiple mosfet models. All the results will be in the error log.

Read “measure” in LTspice help to become familiar with it.

Pointing with the mouse for measurements is not only a pain but imprecise..

eT

 

[eTech]

Hi

Here is an example:

Notice that I named the wires G, D, S. This is to use friendly names and to prevent the wire names from changing.

eT