Re: defining special kind of behavioral for current controlled oscilator in ltspice
On Sun, Mar 16, 2025 at 09:13 AM, Tony Casey wrote:
Typically, the TUNE coil will be 10s of mH and FM coil will be about 10uH. ...
This implies that both inputs might respond to current, unless the TUNE coil has enough resistance which is stable and predictable.
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Andy
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Re: defining special kind of behavioral for current controlled oscilator in ltspice
On Sun, Mar 16, 2025 at 05:15 AM, john23 wrote:
How sould I use MODULATE to define this unique behavior?
john23,
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I uploaded "YIG VCO.asc" to the "Temp" directory.? It models what you apparently wanted.? It has two inputs and one output.
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The "Coarse" input is for your "TUNE" signal that sets the center frequency.? The "Fine" input is for your "FM" signal that modulates its frequency around the center.? Both inputs have infinite bandwidth.
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Both inputs are ideal, so you should add whatever is needed to model each of their electrical characteristics:
- The "Coarse" (or Tune) input is infinite impedance.? If you know its input impedance, connect it in parallel, between the two input pins.
- The "Fine" (or FM) input is zero impedance.? If you know its input impedance, connect it IN SERIES with that input.
- In simulations, both inputs should be given a ground reference, not left floating.
- Both inputs have infinite bandwidth.? Add your own filtering if needed.
The output is +10 dBm when terminated in an external 50 ohms load.? The schematic I uploaded has a 50 ohm load, so remove that when driving something else that provides a termination.
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Andy
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Re: How to create IEC 61000-4-5 surge waveform in time & s behavioral ?
On Fri, Mar 14, 2025 at 06:35 PM, Tony Casey wrote:
On 14/03/2025 11:30, Andy I via groups.io wrote:
Tony uploaded "IEC_61000-4-2_Test.zip", but it has a symbol that LTspice might not have and can't be opened in older versions.
Oops. Zip file updated with symbol.
--
Regards,
Tony
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Just to note, in the latest LTspice 24.1.5, it will have the following message... It seems 'SCOPEDATA=' is forced to replace the 'file='.
Looks like, compatible issue between newer & older...was used to the older XVII...
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"Monotonically increasing value expected. You may want to use SCOPEDATA=<filename> instead. (See the LTspice help for more details.)
1.00E-09,0.9088###>
1.00E-09<###,0.9110"
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And, Thanks for the inspiration of varistors.
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Re: Parts Number Re-numbering
On Sun, Mar 16, 2025 at 07:48 PM, Hidehiko Komachi - JA9MAT wrote:
I heard "shift+ctrl+alt+R" is available.
But no change appear.
Did anything happen?? Was there a pop-up window asking you to confirm?
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If no pop-up window, then perhaps you were not using Windows, or another program intercepted that key combination, or you had another key accidentally pressed or missed one of the four.? When I tried it just now, my first two attempts failed to make the pop-up window, but I tried again - more carefully - and it worked.
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After that, a change can happen only if the part numbers need to be re-numbered.? If they are already numbered the way it wants, you won't see anything change after clicking OK in response to the pop-up confirmation.
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If you have a small number of parts, you can change them one at a time, of course.
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Andy
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Re: Parts Number Re-numbering
Right-click on the number, such as R1. An
editing pane opens where you can change it to anything you like,
within reason.
On 2025-03-16 23:36, Hidehiko Komachi -
JA9MAT via groups.io wrote:
Sorry for FAQ.
How can I renumber the parts number?
I heard "shift+ctrl+alt+R" is available.
But no change appear.
?
Hidehiko JA9MAT.
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
*unquestionably - it's religion
|
Parts Number Re-numbering
Sorry for FAQ.
How can I renumber the parts number?
I heard "shift+ctrl+alt+R" is available.
But no change appear.
?
Hidehiko JA9MAT.
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Re: defining special kind of behavioral for current controlled oscilator in ltspice
On 16/03/2025 13:31, Andy I via
groups.io wrote:
Two ports, really?? I count three.
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Add the Tune and FM inputs, to produce a single
frequency-controlling voltage.? You have many ways to add
signals, including a B-source.? You need to decide on the input
resistance to use, for your Tune and FM ports.
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Then connect their sum, to the FM input of the MODULATE
component.
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Set it's Mark and Space parameters to have the right scale
(1.2 GHz/V) and offset.? This is simple Algebra.? It's very
basic.
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Depending on what john23 is wanting to model, it might be necessary
to actually model the TUNE and FM circuits. They are both connected
to coils internally, so the inductances might need to be included,
particularly if the YIG oscillator is in a frequency control loop or
synthesiser. Typically, the TUNE coil will be 10s of mH and FM coil
will be about 10uH. (They also normally have internal heaters too,
with additional connections, but that has not been mentioned.)
Coo, this brings backs memories from the 1980s.
--
Regards,
Tony
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Re: defining special kind of behavioral for current controlled oscilator in ltspice
Two ports, really?? I count three.
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Add the Tune and FM inputs, to produce a single frequency-controlling voltage.? You have many ways to add signals, including a B-source.? You need to decide on the input resistances to use, for your Tune and FM ports.
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Then connect their sum, to the FM input of the MODULATE component.
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Set its Mark and Space parameters to have the right scale (1.2 GHz/V) oops! (0.7 GHz/V) and offset.? This is simple Algebra.? It's very basic.
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Andy
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Re: defining special kind of behavioral for current controlled oscilator in ltspice
Hello , My device has two ports .I have tested? its functionality in the lab and I saw the following behavior:
1. no voltage? on both ports-> output is 8GHz? 10dBm
2. 2V on tune ->output is 9.4Ghz 10dBm
3.each 1mA on FM input is adding 100Khz.
How sould I use MODULATE to define this unique behavior?
Thanks.
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Take a look at the files I just uploaded to Files/Temp
A simple implementation of what I believe is a corrected form of Pascal's thermal expression,
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Dave
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From: [email protected] <[email protected]>
On Behalf Of pilou via groups.io
Sent: Saturday, March 15, 2025 1:11 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] "Physical" PTC model
?
Thanks a lot for all your message.
But, excuses me for my ignorance, all theses modification have to be done in the model ?
Sorry but I don't know where.
Maybe can you upload your files ?
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We would have a MUCH better idea of exactly where to apply them, if YOU would upload YOUR models.
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From: [email protected] <[email protected]>
On Behalf Of pilou via groups.io
Sent: Saturday, March 15, 2025 1:11 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] "Physical" PTC model
?
Thanks a lot for all your message.
But, excuses me for my ignorance, all theses modification have to be done in the model ?
Sorry but I don't know where.
Maybe can you upload your files ?
|
Thanks a lot for all your message.
But, excuses me for my ignorance, all theses modification have to be done in the model ?
Sorry but I don't know where.
Maybe can you upload your files ?
Thanks a lot in advance
|
Oh, I forgot, you don¡¯t need parentheses around emax, either
?????????????? V={1/(1/emax+0.5*(1+tanh((v(tptc)-ts)/c)))}
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From: [email protected] <[email protected]>
On Behalf Of Bell, Dave via groups.io
Sent: Saturday, March 15, 2025 12:05 PM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] "Physical" PTC model
?
Maybe some help, Pascal:
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I got this to compile and ¡°run¡± without errors, as below:
First, to fill in some unknown values:
?????????????? .params emax=10 c=5 ts=2
Made a voltage source to create and set a value for node ¡°tptc¡±
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Then applying your equation to a behavioral voltage source (BV) in the F2 menu:
?????????????? V={1/(1/(emax)+0.5*(1+tanh((v(tptc)-ts)/c)))}
(This syntax didn¡¯t work with a normal V source.)
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One set of curly braces surrounding everything that needs to be evaluated at run time.
Removing the square brackets? around ¡°v¡± in v(tptc)
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The BV source put out about 902mV, if that makes any sense in your circuit¡
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Dave
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On Sat, Mar 15, 2025 at 11:07 AM, John Woodgate wrote:
I can tell you that the error messages do not mean that there is a problem with the simulation. For example, a node connected only to a current source, which has infinite impedance, appears?
not to be connected to anything.
Hello,
thanks a lot for your reply,
Ok I understand, it seems logical.
Error: undefined symbol in: "1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
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Maybe some help, Pascal:
?
I got this to compile and ¡°run¡± without errors, as below:
First, to fill in some unknown values:
?????????????? .params emax=10 c=5 ts=2
Made a voltage source to create and set a value for node ¡°tptc¡±
?
Then applying your equation to a behavioral voltage source (BV) in the F2 menu:
?????????????? V={1/(1/(emax)+0.5*(1+tanh((v(tptc)-ts)/c)))}
(This syntax didn¡¯t work with a normal V source.)
?
One set of curly braces surrounding everything that needs to be evaluated at run time.
Removing the square brackets? around ¡°v¡± in v(tptc)
?
The BV source put out about 902mV, if that makes any sense in your circuit¡
?
Dave
?
?
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From: [email protected] <[email protected]>
On Behalf Of pilou via groups.io
Sent: Saturday, March 15, 2025 11:16 AM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] "Physical" PTC model
?
On Sat, Mar 15, 2025 at 11:07 AM, John Woodgate wrote:
I can tell you that the error messages do not mean that there is a problem with the simulation. For example, a node connected only to a current source, which has infinite impedance, appears?
not to be connected to anything.
Hello,
thanks a lot for your reply,
Ok I understand, it seems logical.
Error: undefined symbol in: "1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
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I can't diagnose that, unfortunately.
On 2025-03-15 18:15, pilou via
groups.io wrote:
On Sat, Mar 15, 2025 at 11:07 AM, John Woodgate wrote:
I can tell you
that the error messages do not mean that there is a problem
with the simulation. For example, a node connected only to a
current source, which has infinite impedance, appears? not
to be connected to anything.
Hello,
thanks a lot for your reply,
Ok I understand, it seems logical.
But how about the
Error: undefined symbol in:
"1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
?
?
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
*unquestionably - it's religion
|
Perhaps it¡¯s the square brackets in ¡°(°Ú±¹±Õ(³Ù±è³Ù³¦)¡±
?
Dave
?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]>
On Behalf Of pilou via groups.io
Sent: Saturday, March 15, 2025 11:16 AM
To: [email protected]
Subject: EXTERNAL: Re: [LTspice] "Physical" PTC model
?
On Sat, Mar 15, 2025 at 11:07 AM, John Woodgate wrote:
I can tell you that the error messages do not mean that there is a problem with the simulation. For example, a node connected only to a current source, which has infinite impedance, appears?
not to be connected to anything.
Hello,
thanks a lot for your reply,
Ok I understand, it seems logical.
Error: undefined symbol in: "1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
|
Hello,
? ? It's poorly coded. will take time to examine everything.
On Sat, Mar 15, 2025 at 2:15 PM, pilou via groups.io <pilou@...> wrote: On Sat, Mar 15, 2025 at 11:07 AM, John Woodgate wrote:
I can tell you that the error messages do not mean that there is a problem with the simulation. For example, a node connected only to a current source, which has infinite impedance, appears? not to be connected to anything.
Hello,
thanks a lot for your reply,
Ok I understand, it seems logical.
But how about the
Error: undefined symbol in: "1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
?
?
|
On Sat, Mar 15, 2025 at 11:07 AM, John Woodgate wrote:
I can tell you that the error messages do not mean that there is a problem with the simulation. For example, a node connected only to a current source, which has infinite impedance, appears? not to be connected to anything.
Hello,
thanks a lot for your reply,
Ok I understand, it seems logical.
But how about the
Error: undefined symbol in: "1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
?
?
|
I can tell you that the error messages do not
mean that there is a problem with the simulation. For example, a
node connected only to a current source, which has infinite
impedance, appears? not to be connected to anything.
On 2025-03-15 17:53, pilou via
groups.io wrote:
Hello to the community,
I'm very interested by the "PTC Thermistors Physical model"
found in
and I have two questions about it.
?
1) When I try to simulate the example ptc_veijola2.asc it
throw me several errors:
LTspice 24.0.12 for Windows
Circuit: * C:\users\pascal\xxx\ptc_veijola2.asc
Start Time: Sat Mar 15 18:34:27 2025
Questionable use of curly braces in "begb 0 egb
?i={1/(1/{emax}+0.5*(1+tanh((v(tptc)-{ts})/{c})))}"
? ? Error: undefined symbol in:
"1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
solver = Alternate
Maximum thread count: 8
tnom = 27
temp = 27
method = modified trap
ERROR: Node U1:N003 is floating and connected to current
source B:U1:V
Total elapsed time: 0.575 seconds.
Can you help me with that ?
?
2) I would want to simulate this PTC to "measure" a MOSFET
case's temperature. In my case the mosfet have an extra pin
that output a voltage proportional to case's temperature.
The above PTC model take the ambient temperature and have a
third pin to reflect internal temperature.
Is it possible to add an extra pin to be linked to the
mosfet temperature pin ?
?
Thanks a lot in advance,
Pascal
?
--
OOO - Own Opinions only
If something is true:
* as far as we know - it's science
*for certain - it's mathematics
*unquestionably - it's religion
|
Hello to the community,
I'm very interested by the "PTC Thermistors Physical model" found in
and I have two questions about it.
?
1) When I try to simulate the example ptc_veijola2.asc it throw me several errors:
LTspice 24.0.12 for Windows
Circuit: * C:\users\pascal\xxx\ptc_veijola2.asc
Start Time: Sat Mar 15 18:34:27 2025
Questionable use of curly braces in "begb 0 egb ?i={1/(1/{emax}+0.5*(1+tanh((v(tptc)-{ts})/{c})))}"
? ? Error: undefined symbol in: "1/(1/(emax)+0.5*(1+tanh(([v](tptc)-(ts))/(c))))"
solver = Alternate
Maximum thread count: 8
tnom = 27
temp = 27
method = modified trap
ERROR: Node U1:N003 is floating and connected to current source B:U1:V
Total elapsed time: 0.575 seconds.
Can you help me with that ?
?
2) I would want to simulate this PTC to "measure" a MOSFET case's temperature. In my case the mosfet have an extra pin that output a voltage proportional to case's temperature.
The above PTC model take the ambient temperature and have a third pin to reflect internal temperature.
Is it possible to add an extra pin to be linked to the mosfet temperature pin ?
?
Thanks a lot in advance,
Pascal
?
|
John Woodgate
Hidehiko Komachi - JA9MAT
Tony Casey
Bell, Dave