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I want to simulate a circuit and display the current directly in the schematic. However I am only able to display the voltage.

enter image description here

Here you can see an example where someone actually displayed the current as well. So it is must be possible.

enter image description here

I am using the mac version, maybe it's is only available in the windows version. I already spent hours on google...

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  • \$\begingroup\$ As one of the answerer and seeing that this is your first question - while it is important to mark answers as accepted, please don't be pressured into marking an answer that does not actually answer the question. I don't feel that my answer currently does that. \$\endgroup\$ – pipe Aug 6 '16 at 20:09
  • \$\begingroup\$ Yes you are right it doesn't. Just wanted to show some thankfulness for your time. I undid it. \$\endgroup\$ – Peter Aug 6 '16 at 20:40
  • \$\begingroup\$ Have you found a solution? I'm still looking... \$\endgroup\$ – Flying Swissman Oct 10 '18 at 21:02
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It's a little stupid, but here's how it's done:

  1. Place your voltage label, essentially anywhere.
  2. Right-click on the label. This may be difficult if Apple still doesn't understand that more buttons is more flexible - in any case, there must be an OSX-specific solution to that, because it's used a lot in LTspice.
  3. Now you can put whatever expression you want for the label, and the popup shows a list of valid nodes voltages and currents. enter image description here
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    \$\begingroup\$ Step 2 doenst work on the mac. I can't open the menu "Display Data". Do you know a shortcut for that menu? \$\endgroup\$ – Peter Aug 6 '16 at 19:38
  • \$\begingroup\$ @Jan No, I don't. When I hover with the cursor over a node it literally tells me "Right click to edit the displayed expression.". A quick google tells me that you need to use a "real" right-click, not the control-left or command-left or something. Maybe that's the problem? \$\endgroup\$ – pipe Aug 6 '16 at 19:46
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If this question still persists: the only way I have found to be able to do this is simply run the Windows version through Wine on Mac. It seems to be fairly stable. The interesting part is that once schematic is updated device current OP data label using the Wine version, it will still work in the native Mac version.

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A bit late, but perhaps useful for someone using LTspice on Mac:

  1. In LTspice, place an .op data label and save/close the file.
  2. Open the .asc with a text editor and locate a line that starts with DATAFLAG.
  3. Change the text inside the double quotes to another expression. E.g. exact voltage at the connected net as "$", "round($)" with zero decimals, "round($*1k)/1k" with three decimals, etc. -- and currents can be displayed through a component as e.g. "I(R1)", applying the same rounding technique if needed. More examples here. Save/close the file.
  4. Re-open the file in LTspice. The data label will display as ??? initially, but just run the .op analysis and see the numbers.
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  • \$\begingroup\$ Wow, you can't use the GUI with a mac? I wonder why. \$\endgroup\$ – Bort May 8 at 13:45
  • \$\begingroup\$ The GUI on a mac seems ok for everything but this feature. \$\endgroup\$ – Janus Bo Andersen May 8 at 19:09
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Seems easy enough to me, using the Windows version. I just hit "t" to call up a text dialog box, enter "1mA" into the box, click on the "vertical text" check box if I want the text to be vertical, and then lay it down somewhere on the schematic.

You can mess around with things a little more than that. For example, you can grab the text and use ctrl-E or ctrl-R to rotate or flip it around. But that only changes the anchor point around. You still can only get horizontal or vertical text in one form, each.

In the example you show where the current is added, the text is blue and uses even numbers (not precise ones with lots of digits.) Which means it is consistent with a text addition, like I described. Unfortunately, I don't have a mac, so I can't check it there.

EDIT: You now have two very different methods to try out, given the other post here (at this time) on this! Great!

EDIT AGAIN: On Windows, you can move your mouse over a wire and the pointer will change from a thin-lined cross to a red "probe" symbol. If you hover over the node with the red probe visible as the mouse cursor and then right click your mouse, you get an option list showing. Among the options, I see something that says "Place .op Data Label." If you select that one, you'll get the label on the node that the other answerer talked to you about.

Now, you can hover the mouse over that newly added label, see the mouse cursor change to a 'text bar' cursor type, and if you right click now you will get the display of nodes he also mentioned. (Under Windows, anyway.)

Does that help you on the Mac, at all?

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    \$\begingroup\$ Note that you can (and probably should) use the round() function in the node probes, to get those "round" numbers. For example, round(1k*$)/1k should work. \$\endgroup\$ – pipe Aug 6 '16 at 19:48
  • \$\begingroup\$ I had imagined that the author of the second schematic had done what I do: place design assumption values or rough expected values on a node. It would be "noisy" (except perhaps while checking things out) to litter a schematic with .OP generated figures. To me, anyway. I write my schematics for others to read and understand. So the labels are there to let them (and me, later on) know where my brain was at. Not where Spice calculates some simulated value. \$\endgroup\$ – jonk Aug 6 '16 at 19:51
  • \$\begingroup\$ You're likely right in this case - Except for the voltages, the numbers are a bit too round. Out of curiosity I made the same simulation and I get 1.01 mA in, 3.26 µA current in the middle node, and 1.06 mA on the right side. \$\endgroup\$ – pipe Aug 6 '16 at 19:58
  • \$\begingroup\$ Yeah. I take your point about 637mV, for example. I do tend to put down my expected voltage values to the millivolt, though. So, for example, I might start out telling myself \$V_{be}\$ = 0.7V at Ic = 4mA. It's 60mV per decade Ic change from there, so at 1mA the voltage works out to -36mV from there. I then label it 664mV. Does that make sense? It's how I work, anyway. \$\endgroup\$ – jonk Aug 6 '16 at 20:04
  • \$\begingroup\$ Ok so this guy probably used plain text lables. Nevertheless when I hover with the cursor over a label there is no "right click to edit displayed expression". That's weird and makes ltspice almost unusable on the mac. \$\endgroup\$ – Peter Aug 6 '16 at 20:05
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On a PC I right click also to change the value of a component. I guess you have a way of doing this on the Mac as well. Try to do the same thing with the label in step 2 of pipe's answer.

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the way you can do this is by looking at the log files created after you run the simulation, they are available at the same path as the files. I now its kind of late but hope this helps

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  • \$\begingroup\$ Can you also share a snapshot of the values where it will be shared? If current needs to be monitored dynamically, how would one address it? \$\endgroup\$ – Umar Jan 24 '17 at 15:49
  • \$\begingroup\$ Just looking at the log files won't put the value on the schematic, will it? \$\endgroup\$ – dim Jan 24 '17 at 20:51
  • \$\begingroup\$ Yes, I didn't realise that you wanted it to be displayed dynamically. Sorry for the trouble but I can share the screenshot of the log file if it helps. \$\endgroup\$ – Farhan Javeed Jan 25 '17 at 16:11

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