I am trying to work with the CD4000_v.lib and am getting errors when trying to run. Would someone provide me some guidance as to what is set up in error?
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File uploaded to temp: CD_test.zip
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This is using the CD4013 as a counter. I have included the latest CD4000_v.lib and the CD4013B symbol from the files section to make it easy.
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Re: Simulation runs very slowly: test.asc
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Re: creating PNP caracteristicsby sweeping plot in LTspice from a circuit I built
On Tue, Apr 1, 2025 at 02:20 PM, john23 wrote:
Hello,I would like to try and implement the caracteristics with the circuit I made (attached)
Do you wish to sweep the curves of this one unique circuit?? Or do you wish to sweep the curves of a PNP transistor?
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If you want to plot curves of this one unique circuit, then first you need to know what are the curves that you want to sweep.? What properties of this one circuit do you want to see in a plot?
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PNP have current structure where we can see by the current slope that PNP is saturated or linear.
How can we create such current plot?
See my circuits in "PNP_sweep.zip" in the Temp folder.? They plot the Ic/Ib and Ic/Vbe curves for just the PNP transistor.? The Ic/Ib plot is the one you most often see, because the transfer from Vbe to Ic is strongly nonlinear.? The Ic/Ib plot is also the one that corresponds to your photo "2.png" that you uploaded yesterday inside your "31_03_25.zip".
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Andy
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Re: creating PNP caracteristicsby sweeping plot in LTspice from a circuit I built
Your message is confused, your.ASC is
unsuitable. Looking at currents will not tell you about
saturation, which is when Vce drops to a very low value, like
0.4 V or less. It never does that in your .ASC.
On 2025-04-01 19:20, john23 via
groups.io wrote:
Hello,I would like to try and implement the caracteristics
with the circuit I made (attached)
By sweeping V1 (emitter source I see 0 current increases
after Vbe>0.7)
Hopwever I cant see if the PNP is in saturation or linear
states.
PNP have current structure where we can see by the current slope
that PNP is saturated or linear.
How can we create such current plot?
Thanks.?
?
--
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
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Re: creating PNP caracteristicsby sweeping plot in LTspice from a circuit I built
Hello,I would like to try and implement the caracteristics with the circuit I made (attached)
By sweeping V1 (emitter source I see 0 current increases after Vbe>0.7)
Hopwever I cant see if the PNP is in saturation or linear states.
PNP have current structure where we can see by the current slope that PNP is saturated or linear.
How can we create such current plot?
Thanks.?
?
/g/LTspice/files/Temp/Draft2%20%281%29.zip
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Re: Simulation runs very slowly: test.asc
Thanks Andy, you beat me to it. ?
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From: [email protected] <[email protected]> On Behalf Of Andy I via groups.io
Sent: Tuesday, April 1, 2025 11:51 AM
To: [email protected]
Subject: Re: [LTspice] Simulation runs very slowly: test.asc? On Tue, Apr 1, 2025 at 11:23 AM, eetech00 wrote: Is the 1 ohm resistor the load?
It is part of what makes it a current regulator.? The LM317 drives its output pin until the voltage between its OUT and ADJ pins is 1.25 V which is its internal "reference" voltage.? If the ADJ pin was connected directly to the downstream end of the 1 ohm resistor, it would source 1.25 Amps.? But there is the 402 ohm resistor between the downstream end of the 1 ohm resistor and the ADJ pin, and we know there is (approx.) 1 V dropped across that resistor due to the current through the MOSFET, so that leaves 1.25 - 1.0 = 0.25 V across the 1 ohm resistor.? Hence, the LM317 drives 250 mA from its OUT pin.? A small amount of it (2.5 mA) also flows through the 402 ohm resistor to the MOSFET, but the bulk of the current (247 mA) continues to the string of diodes = the load.
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Re: Simulation runs very slowly: test.asc
On Tue, Apr 1, 2025 at 11:23 AM, eetech00 wrote:
Is the 1 ohm resistor the load?
It is part of what makes it a current regulator.? The LM317 drives its output pin until the voltage between its OUT and ADJ pins is 1.25 V which is its internal "reference" voltage.? If the ADJ pin was connected directly to the downstream end of the 1 ohm resistor, it would source 1.25 Amps.? But there is the 402 ohm resistor between the downstream end of the 1 ohm resistor and the ADJ pin, and we know there is (approx.) 1 V dropped across that resistor due to the current through the MOSFET, so that leaves 1.25 - 1.0 = 0.25 V across the 1 ohm resistor.? Hence, the LM317 drives 250 mA from its OUT pin.? A small amount of it (2.5 mA) also flows through the 402 ohm resistor to the MOSFET, but the bulk of the current (247 mA) continues to the string of diodes = the load.
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Andy
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Re: Simulation runs very slowly: test.asc
On Tue, Apr 1, 2025 at 07:40 AM, Andy I wrote:
On Tue, Apr 1, 2025 at 08:51 AM, Christopher Paul wrote:
It¡¯s unclear to me which of the four separate circuits you are referring to, or why you are suggesting a reconfiguration and what goal you are pursuing. All are configured as I intended. They are independent of one another except for sharing a power supply.
I think eT was getting confused about the fact that there were two current sources, which he thought both fed current into the string of diodes.? They don't, of course.? (Even if they did, they do not conflict or fight.? Current sources can be directly added without problem.)
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Yes...i'm confused with the circuit configuration.
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Re: Simulation runs very slowly: test.asc
On Tue, Apr 1, 2025 at 05:51 AM, Christopher Paul wrote:
It¡¯s unclear to me which of the four separate circuits you are referring to, or why you are suggesting a reconfiguration and what goal you are pursuing.
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My only goal is to try to help. But the circuit doesn't make sense. I think you are comparing the behavior of the groups of circuits. But what is the final circuit supposed to do?
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Is the 1 ohm resistor the load?
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Re: Simulation runs very slowly: test.asc
On Tue, Apr 1, 2025 at 08:51 AM, Christopher Paul wrote:
It¡¯s unclear to me which of the four separate circuits you are referring to, or why you are suggesting a reconfiguration and what goal you are pursuing. All are configured as I intended. They are independent of one another except for sharing a power supply.
I think eT was getting confused about the fact that there were two current sources, which he thought both fed current into the string of diodes.? They don't, of course.? (Even if they did, they do not conflict or fight.? Current sources can be directly added without problem.)
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The op-amp+MOSFET current source controls the 100-times-larger LM317A current source, by controlling its voltage sensing pins (the voltage between its OUT and ADJ pins).? We don't know exactly why Chris has it arranged that way, but I'm guessing it is either to toggle the LM317's current source on and off, or to adjust its current level.
Although we still don¡¯t know, the simulation completes and runs (acceptably) slowly with Andy¡¯s suggestion of the alternate solver.
You can speed up the simulations.? With the Alternate solver, or the pull-down resistor, LTspice wastes a lot of time trying (and failing) to find the initial operating point.? By examining the results in the Error Log file, you can see which of its algorithms failed, and then add appropriate .OPTIONS commands to skip those algorithms and save time.? For example:
? ? .OPTIONS NoOpIter GminSteps=0 SrcSteps=0
makes it go straight to the Pseudo-Tran algorithm, which is the only one that succeeded with just the Alternate solver.? If I remember correctly, the Alternate Source Stepping algorithm succeeded after adding the pulldown resistor, so omit "SrcSteps=0" in that case.
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See LTspice's Help > LTspice > Dot Commands > .OP -- Find the DC Operating Point.? The information on that page applies to all simulations, not only the ones that have an ".OP" simulation command.
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I don't know what causes the first two or three algorithms to fail.? Sometimes that just happens and we need to live with it.? That is why LTspice has four algorithms, in case some of them fail.
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Andy
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Re: Simulation runs very slowly: test.asc
On Tue, Apr 1, 2025 at 05:03 AM, Tony Casey wrote:
Threaded discussion list view can be enabled in other email clients besides Thunderbird, including Gmail, Kmail, Outlook and Windows Mail. In Gmail, Outlook and Windows Mail it is called "Conversation" view, but it needs configuring in most clients and is best used when filters or rules are applied to your inbox(es) to move certain messages to other folders.
Gmail's "Conversation" view is very much NOT the same as Thunderbird's Threaded view.? Gmail ignores the same header line that identifies message threading that Thunderbird uses.? When someone hijacks a topic and changes the Subject line, Gmail always puts it into a separate topic in Gmail, unlike what Thunderbird does.? (Actually I think that is a combination of both the Subject line and another hidden header line.? But it definitely differs from Thunderbird's view.)
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My recollection is that Outlook also ignored threading (conversations were grouped but not threaded), and used something like the Subject line to identify conversations.? But I have not used Outlook in many years.
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My first home internet email reader had a proper threaded view, which I really missed when I eventually changed to different email programs.? And still miss.
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I am sometimes guilty of replying to the wrong topic in a thread.? Sometimes I pick a random topic to reply to (often it's either the first or the last), which probably does not look right in a properly threaded message view.? I should stop doing that.
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Andy
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Re: Simulation runs very slowly: test.asc
It¡¯s unclear to me which of the four separate circuits you are referring to, or why you are suggesting a reconfiguration and what goal you are pursuing. All are configured as I intended. They are independent of one another except for sharing a power supply. ? The purpose of the schematic is to try to isolate the aspect of the right-most circuit (which is the one I¡¯m really interested in) which is causing the simulation problem. Although we still don¡¯t know, the simulation completes and runs (acceptably) slowly with Andy¡¯s suggestion of the alternate solver. ?
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From: [email protected] <[email protected]> On Behalf Of eetech00 via groups.io
Sent: Monday, March 31, 2025 7:59 PM
To: [email protected]
Subject: Re: [LTspice] Simulation runs very slowly: test.asc? I haven't tried this but, then the anode of the top diode should connect to the LM317 current regulator output and the mosfet drain should connect to the cathode of the bottom diode in the string(?)
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Re: Simulation runs very slowly: test.asc
Just a FYI:
Threaded discussion list view can be enabled in other email clients
besides Thunderbird, including Gmail, Kmail, Outlook and Windows
Mail. In Gmail, Outlook and Windows Mail it is called "Conversation"
view, but it needs configuring in most clients and is best used when
filters or rules are applied to your inbox(es) to move certain
messages to other folders.
--
Regards,
Tony
On 31/03/2025 02:13, Andy I via
groups.io wrote:
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It won't affect
most of you, and it does not change the problem that it hijacked
another topic.? Sorry to you Thunderbird email users, but we are
stuck with that.
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Re: Simulation runs very slowly: test.asc
On Mon, Mar 31, 2025 at 07:59 PM, eetech00 wrote:
I haven't tried this but, then the anode of the top diode should connect to the LM317 current regulator output and the mosfet drain should connect to the cathode of the bottom diode in the string(?)
I think that would not make sense, because there's about a 100 to 1 difference in the two current limiters.
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The op-amp+MOSFET part is a (logical) input into the '317 regulator.? NOT meant to drive the diode load, and it does not drive the diodes at all.
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Andy
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Re: Simulation runs very slowly: test.asc
I haven't tried this but, then the anode of the top diode should connect to the LM317 current regulator output and the mosfet drain should connect to the cathode of the bottom diode in the string(?)
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Re: Simulation runs very slowly: test.asc
The op-amp+FET sinks?current downwards.
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The LM317A sources current to the diodes, plus the FET.? They don't compete.
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There are 2 orders of magnitude difference between the two current regulators.
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I think the FET sink sets the drop across a resistor, 'tuning' the much greater current regulated by the '317.
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Andy
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Re: Simulation runs very slowly: test.asc
Andy found that the Alternate Solver is a solution, although the simulation run is anything but lightning-fast. He posits that some form of very high frequency (numerical) oscillation is slowing things down. ?
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From: [email protected] <[email protected]> On Behalf Of eetech00 via groups.io
Sent: Monday, March 31, 2025 6:59 PM
To: [email protected]
Subject: Re: [LTspice] Simulation runs very slowly: test.asc? On Mon, Mar 31, 2025 at 02:14 PM, Christopher Paul wrote: eetech00, I¡¯m afraid I don¡¯t understand. ? From what I can see, each of the three diode strings is driven by a single current regulator. Maybe you could you describe your concerns using component reference designators? ?
You have three groups of circuits, but I'll refer to one group. The opamp and mosfet forms a basic Volt to current converter and its controlling current thru the diodes. The LM317 is also configured as a current regulator and it also (trying) control current thru the diodes. That's what I think is causing the simulation convergence problems.
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Re: Simulation runs very slowly: test.asc
On Mon, Mar 31, 2025 at 02:14 PM, Christopher Paul wrote:
eetech00, I¡¯m afraid I don¡¯t understand.
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From what I can see, each of the three diode strings is driven by a single current regulator. Maybe you could you describe your concerns using component reference designators?
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You have three groups of circuits, but I'll refer to one group.
The opamp and mosfet forms a basic Volt to current converter and its controlling current thru the diodes.
The LM317 is also configured as a current regulator and it also (trying) control current thru the diodes.
That's what I think is causing the simulation convergence problems.
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Re: Simulation runs very slowly: test.asc
eetech00, I¡¯m afraid I don¡¯t understand. ? From what I can see, each of the three diode strings is driven by a single current regulator. Maybe you could you describe your concerns using component reference designators? ?
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From: [email protected] <[email protected]> On Behalf Of eetech00 via groups.io
Sent: Monday, March 31, 2025 4:58 PM
To: [email protected]
Subject: Re: [LTspice] Simulation runs very slowly: test.asc? The circuit run fine if its connected correctly. The way it is connected, the two current regulators are in conflict with each other, since they are both trying to regulate current to the same load (the diodes). Use two separated current loads, one for each regulator.
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Re: Simulation runs very slowly: test.asc
Chris
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The circuit run fine if its connected correctly.
The way it is connected, the two current regulators are in conflict with each other, since they are both trying to regulate current to the same load (the diodes). Use two separated current loads, one for each regulator.
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DerekK
John Woodgate
Tony Casey