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LtSpice something, strange happenings.

Started by Jamie September 17, 2012
I don't use Ltspice or any spice that much however, last night I pulled 
something out of my old sketch books and plotted it to LTspice, with a 
little change with values to be used for a specific task.

I noticed something strange. As you hover over the nodes, it is 
convenient to look at the lower left corner to get information about
that node. Things like voltage, current etc. However, with a specific
drawing(this one), it is showing some off the wall or should I say off 
the map, readings in measuring units that are wrong and symbols that 
have no meaning for the scale unit.

   Not only that, the value that is displayed down there is not even 
related to what is at the node but dig this, when
I double click on any of those nodes to show it in the graph above, the 
graph is correct, but the bottom view is still wrong, grossly wrong.

  Tonight, I popped in a simple drawing ect, it's fine.. But reloaded 
this one particular drawing, and it's all over the map down
below?

  There must be something in there that is confusing the hell out of 
LTSpice?

  I have version 4.15s if that helps..

  it's not that much of a big deal, I do most of my stuff by hand and a 
few other little programs I have lying around here. Just thought I'd
ask to see if any one else has noticed this?

Jamie

Jamie wrote:
> I don't use Ltspice or any spice that much however, last night I pulled > something out of my old sketch books and plotted it to LTspice, with a > little change with values to be used for a specific task. > > I noticed something strange. As you hover over the nodes, it is > convenient to look at the lower left corner to get information about > that node. Things like voltage, current etc. However, with a specific > drawing(this one), it is showing some off the wall or should I say off > the map, readings in measuring units that are wrong and symbols that > have no meaning for the scale unit. > > Not only that, the value that is displayed down there is not even > related to what is at the node but dig this, when > I double click on any of those nodes to show it in the graph above, the > graph is correct, but the bottom view is still wrong, grossly wrong. > > Tonight, I popped in a simple drawing ect, it's fine.. But reloaded > this one particular drawing, and it's all over the map down > below? > > There must be something in there that is confusing the hell out of > LTSpice? > > I have version 4.15s if that helps.. > > it's not that much of a big deal, I do most of my stuff by hand and a > few other little programs I have lying around here. Just thought I'd > ask to see if any one else has noticed this? >
Did you see a submarine plow up the Guadalupe River, with a Chinese flag? So maybe ... Just kidding. If it's any comfort, the voltages shown down there may not mean much. I am doing sims right now and when I hold the cursor to a node at the top of a 3.3V DC source the text down there reads zero volts. Of course it isn't real, in the display window later it shows correctly. -- Regards, Joerg http://www.analogconsultants.com/
Jamie wrote:
> Joerg wrote: > >> Jamie wrote: >> >>> I don't use Ltspice or any spice that much however, last night I pulled >>> something out of my old sketch books and plotted it to LTspice, with a >>> little change with values to be used for a specific task. >>> >>> I noticed something strange. As you hover over the nodes, it is >>> convenient to look at the lower left corner to get information about >>> that node. Things like voltage, current etc. However, with a specific >>> drawing(this one), it is showing some off the wall or should I say off >>> the map, readings in measuring units that are wrong and symbols that >>> have no meaning for the scale unit. >>> >>> Not only that, the value that is displayed down there is not even >>> related to what is at the node but dig this, when >>> I double click on any of those nodes to show it in the graph above, the >>> graph is correct, but the bottom view is still wrong, grossly wrong. >>> >>> Tonight, I popped in a simple drawing ect, it's fine.. But reloaded >>> this one particular drawing, and it's all over the map down >>> below? >>> >>> There must be something in there that is confusing the hell out of >>> LTSpice? >>> >>> I have version 4.15s if that helps.. >>> >>> it's not that much of a big deal, I do most of my stuff by hand and a >>> few other little programs I have lying around here. Just thought I'd >>> ask to see if any one else has noticed this? >>> >> >> >> Did you see a submarine plow up the Guadalupe River, with a Chinese >> flag? So maybe ... >> >> Just kidding. If it's any comfort, the voltages shown down there may not >> mean much. I am doing sims right now and when I hold the cursor to a >> node at the top of a 3.3V DC source the text down there reads zero >> volts. Of course it isn't real, in the display window later it shows >> correctly. >> > Yeah, I just found out why it does that, if you start the sim at 0 DC > volts, the below display is showing you the initial values. THose could > be all over the place. I guess if you want to know that information it > could be useful :) > > I never used an emulator before. My youngest while in trade school used > Workbench and I didn't really think much of that. When he entered JW for > Electronic Engineering they used something but it sure wasn't LtSpice, > it could of been some other spice program, I don't know. >
What's JW? Not familiar with that but most of my education was overseas.
> All I know is, when he'd come on for the weekends, I'd end up helping > him with homework and getting some lab builds to work correctly.. >
Nothing better than father and son working together on a project. As long as there's a nice cold brewsky afterwards once it all works :-) First time my dad did that with me was early highschool. The oil furnace did its telltale whoopah .. whoopah .. *POOF* and dad said "Son, I'll be off on a biz trip soon so let's go into the dungeon, time for you to learn how to fix that monster". -- Regards, Joerg http://www.analogconsultants.com/
Joerg wrote:

> Jamie wrote: > >>I don't use Ltspice or any spice that much however, last night I pulled >>something out of my old sketch books and plotted it to LTspice, with a >>little change with values to be used for a specific task. >> >>I noticed something strange. As you hover over the nodes, it is >>convenient to look at the lower left corner to get information about >>that node. Things like voltage, current etc. However, with a specific >>drawing(this one), it is showing some off the wall or should I say off >>the map, readings in measuring units that are wrong and symbols that >>have no meaning for the scale unit. >> >> Not only that, the value that is displayed down there is not even >>related to what is at the node but dig this, when >>I double click on any of those nodes to show it in the graph above, the >>graph is correct, but the bottom view is still wrong, grossly wrong. >> >> Tonight, I popped in a simple drawing ect, it's fine.. But reloaded >>this one particular drawing, and it's all over the map down >>below? >> >> There must be something in there that is confusing the hell out of >>LTSpice? >> >> I have version 4.15s if that helps.. >> >> it's not that much of a big deal, I do most of my stuff by hand and a >>few other little programs I have lying around here. Just thought I'd >>ask to see if any one else has noticed this? >> > > > Did you see a submarine plow up the Guadalupe River, with a Chinese > flag? So maybe ... > > Just kidding. If it's any comfort, the voltages shown down there may not > mean much. I am doing sims right now and when I hold the cursor to a > node at the top of a 3.3V DC source the text down there reads zero > volts. Of course it isn't real, in the display window later it shows > correctly. >
Yeah, I just found out why it does that, if you start the sim at 0 DC volts, the below display is showing you the initial values. THose could be all over the place. I guess if you want to know that information it could be useful :) I never used an emulator before. My youngest while in trade school used Workbench and I didn't really think much of that. When he entered JW for Electronic Engineering they used something but it sure wasn't LtSpice, it could of been some other spice program, I don't know. All I know is, when he'd come on for the weekends, I'd end up helping him with homework and getting some lab builds to work correctly.. Jamie
On Sep 17, 3:51=A0pm, Joerg <inva...@invalid.invalid> wrote:
> Jamie wrote: > > Joerg wrote: > > >> Jamie wrote: > > >>> I don't use Ltspice or any spice that much however, last night I pull=
ed
> >>> something out of my old sketch books and plotted it to LTspice, with =
a
> >>> little change with values to be used for a specific task. > > >>> I noticed something strange. As you hover over the nodes, it is > >>> convenient to look at the lower left corner to get information about > >>> that node. Things like voltage, current etc. However, with a specific > >>> drawing(this one), it is showing some off the wall or should I say of=
f
> >>> the map, readings in measuring units that are wrong and symbols that > >>> have no meaning for the scale unit. > > >>> =A0Not only that, the value that is displayed down there is not even > >>> related to what is at the node but dig this, when > >>> I double click on any of those nodes to show it in the graph above, t=
he
> >>> graph is correct, but the bottom view is still wrong, grossly wrong. > > >>> Tonight, I popped in a simple drawing ect, it's fine.. But reloaded > >>> this one particular drawing, and it's all over the map down > >>> below? > > >>> There must be something in there that is confusing the hell out of > >>> LTSpice? > > >>> I have version 4.15s if that helps.. > > >>> it's not that much of a big deal, I do most of my stuff by hand and a > >>> few other little programs I have lying around here. Just thought I'd > >>> ask to see if any one else has noticed this? > > >> Did you see a submarine plow up the Guadalupe River, with a Chinese > >> flag? So maybe ... > > >> Just kidding. If it's any comfort, the voltages shown down there may n=
ot
> >> mean much. I am doing sims right now and when I hold the cursor to a > >> node at the top of a 3.3V DC source the text down there reads zero > >> volts. Of course it isn't real, in the display window later it shows > >> correctly. > > > Yeah, I just found out why it does that, if you start the sim at 0 DC > > volts, the below display is showing you the initial values. THose could > > be all over the place. I guess if you want to know that information it > > could be useful :) > > > =A0I never used an emulator before. My youngest while in trade school u=
sed
> > Workbench and I didn't really think much of that. When he entered JW fo=
r
> > Electronic Engineering they used something but it sure wasn't LtSpice, > > it could of been some other spice program, I don't know. > > What's JW? Not familiar with that but most of my education was overseas. > > > =A0 All I know is, when he'd come on for the weekends, I'd end up helpi=
ng
> > him with homework and getting some lab builds to work correctly.. > > Nothing better than father and son working together on a project. As > long as there's a nice cold brewsky afterwards once it all works :-) > > First time my dad did that with me was early highschool. The oil furnace > did its telltale whoopah .. whoopah .. *POOF* and dad said "Son, I'll be > off on a biz trip soon so let's go into the dungeon, time for you to > learn how to fix that monster". > > -- > Regards, Joerg > > http://www.analogconsultants.com/
shades of "A Christmas Story" and Darren McGavin's character as the famous 'furnace fighter'
"Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> schrieb im 
Newsbeitrag news:osN5s.351$J22.117@newsfe04.iad...
>I don't use Ltspice or any spice that much however, last night I pulled >something out of my old sketch books and plotted it to LTspice, with a >little change with values to be used for a specific task. > > I noticed something strange. As you hover over the nodes, it is convenient > to look at the lower left corner to get information about > that node. Things like voltage, current etc. However, with a specific > drawing(this one), it is showing some off the wall or should I say off the > map, readings in measuring units that are wrong and symbols that have no > meaning for the scale unit. > > Not only that, the value that is displayed down there is not even > related to what is at the node but dig this, when > I double click on any of those nodes to show it in the graph above, the > graph is correct, but the bottom view is still wrong, grossly wrong. > > Tonight, I popped in a simple drawing ect, it's fine.. But reloaded this > one particular drawing, and it's all over the map down > below? > > There must be something in there that is confusing the hell out of > LTSpice? > > I have version 4.15s if that helps.. > > it's not that much of a big deal, I do most of my stuff by hand and a few > other little programs I have lying around here. Just thought I'd > ask to see if any one else has noticed this? > > Jamie
Hello Jamie, LTspice shows the DC-operating point in the left lower corner. This value will be calculated at the beginning before the circuit will be simulated over time. Best regards, Helmut
Helmut Sennewald wrote:

> "Jamie" <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> schrieb im > Newsbeitrag news:osN5s.351$J22.117@newsfe04.iad... > >>I don't use Ltspice or any spice that much however, last night I pulled >>something out of my old sketch books and plotted it to LTspice, with a >>little change with values to be used for a specific task. >> >>I noticed something strange. As you hover over the nodes, it is convenient >>to look at the lower left corner to get information about >>that node. Things like voltage, current etc. However, with a specific >>drawing(this one), it is showing some off the wall or should I say off the >>map, readings in measuring units that are wrong and symbols that have no >>meaning for the scale unit. >> >> Not only that, the value that is displayed down there is not even >>related to what is at the node but dig this, when >>I double click on any of those nodes to show it in the graph above, the >>graph is correct, but the bottom view is still wrong, grossly wrong. >> >> Tonight, I popped in a simple drawing ect, it's fine.. But reloaded this >>one particular drawing, and it's all over the map down >>below? >> >> There must be something in there that is confusing the hell out of >>LTSpice? >> >> I have version 4.15s if that helps.. >> >> it's not that much of a big deal, I do most of my stuff by hand and a few >>other little programs I have lying around here. Just thought I'd >>ask to see if any one else has noticed this? >> >>Jamie > > > Hello Jamie, > > LTspice shows the DC-operating point in the left lower corner. > This value will be calculated at the beginning before the circuit will be > simulated over time. > > Best regards, > Helmut > > >
yeah, I found that out. I don't use it that much. I would bet there is a cursor/marker I can set on the sim to show me where at what point to show the values. Clicking on the nodes are find for value, I some times find it just simpler to look at the values as mouse over the nodes. Thanks. Jamie