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PWL file in LTSPICE XVII not working while working in LT spice IV

 

Hello
LT spice? XVII displays the following cumbersome message in a simulation involving a voltage PWL file:

"trouble stat()'ing PWL file "? (SIC)

the simulation works perfectly in LT spice IV, which reads the PWL file the right way.

I tried several files and they all fail.

Any hint to solve this . Thanks
Re: Sub circuit heat dissipation not showing

John Woodgate
 

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Depend on the definition of 'thing'. For me, 'RMS power' is not a 'thing'. Highland Scots might disagree.

?

With best wishes DESIGN IT IN! OOO ¨C Own Opinions Only

J M Woodgate and Associates Rayleigh England

?

Sylvae in aeternum manent.

?

From: LTspice@... [mailto:LTspice@...]
Sent: Friday, August 5, 2016 6:00 PM
To: [LTspice] group
Subject: Re: [LTspice] Re: Sub circuit heat dissipation not showing

?

?

Nit:

?

? ?"there is **no such thing** as 'RMS power'."

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Well, there is, but you wouldn't find it a useful thing to compute.? As you said, it has no physical significance.? So nobody ever calculates RMS power.

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Andy

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Re: Need help to design a transimpedance amplifier

 

¿ªÔÆÌåÓý

Would you like to look at the Idea i posted in the Temp file(photo amplifier 15A) and somebody else reproduced it with different component values(photo amp) i think you may have to rethink your TIA noise strategy if you understand how it works. ?Please note the following correction:= ?[(wc)**2 = 1/(R1RL)]. ?Please attempt to show that the expression I have just quoted is the notch condition for the op. amp. n/w.
comments are most welcome

Michael

To: LTspice@...
From: LTspice@...
Date: Thu, 4 Aug 2016 11:03:19 +0200
Subject: Re: [LTspice] Re: Need help to design a transimpedance amplifier

?

Check the datasheet for the OPA 2846:
Vn=1.2nV/sqrtHz, In=2.8pA/sqrtHz
that means the OSI (optimum source impedance) is 428 ohms.
The 100k resistors in the non-inverting inputs alone introduce 88uV (@100kHz BW)
What is the transducer's impedance?


Le 04/08/2016 ¨¤ 09:31, t.obulesu@... [LTspice] a ¨¦crit?:
?
Let me say why am looking for new design..
We are currently using the receiver module which has three stages:
1. Trans Impedance stage
2. High Pass filter (HPF) stage
3. Unity gain amplifier (just for inverting the output of the HPF)

Well...we used LM2662 as a -5V supply..
Here on we could see the hell noise below 100kHz..
I couldn't get rid of this noise by using bypass caps..but I could just reduced it..
Yet there is a lot of noise all across the circuit ranging from few kHz to hundreds of MHz...









are the links where I have uploaded couple of documents..

I really don't know what sort of noise it is and from where it is coming...


L'absence de virus dans ce courrier ¨¦lectronique a ¨¦t¨¦ v¨¦rifi¨¦e par le logiciel antivirus Avast.



Re: No XP?

Gunoi Nare
 

As a mater of fact? Andy, I do still run 3.1. on an old 8MHz DELL AT Computer. It is my127 channel logic analyzer.
Resolution of 100pS. Did you see how much something like this kosts? now-a-days? Why shel i scrap it?
So? Mr.Gates & Co. get richer?

You might own an oil well in the back yard but I assure you I do not.

The other days I visited my dentist.? He makes an "Digital Xray' of? my hurting tooth.
A space agedigital machine all bells and whistles.

"Well he said All is OK I can not determine the cause of your pain."

Doc, I said do you still have the 40Year Xray machine, the one that uses film?
Yes,but this one,the digital one is 100 times better.

Doc,lets make a picture on the old machine.
When all was said and done, he exclaimed;
Zum teufel... I did not expect this. There was right there in front of him a crack no larger than
250uM.

how can you explain to a doctor the notion of resolution,sampling rate and so on.


And this is why I stil? keep my HP114t.

they do not make thinks like this any more.


And for Helmut. Yes I did try VIII on Vista. All my work is done on vista.

G


From: "Andy ai.egrps@... [LTspice]"
To: [LTspice] group
Sent: Saturday, August 6, 2016 5:34 PM
Subject: Re: [LTspice] No XP?

?
?I have Windows version 1.? Do you think LTspice works with it?? Should I blast someone at LTC for daring to come up with a program that doesn't?? Does this mean that LTC beats the dust? (or did you mean bites the dust? he-he) ?And, as you imply, does this mean LTC didn't ever do any engineering?

And what about Windows 3.1?? Are you still running it?? Do all your latest programs run on it?

Heck, does it irk you that LTspice -- any version -- isn't compatible with DOS 2.11?

Andy

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Re: No XP?

 

Hello Helmut

I tried to install LTspice XVII under Vista 32b.

I did'nt succeed : nothing happens on the screen..

We can see on LT web site : Ltspice XVII for Windows 7,8 and 10

Regards
PhB
Re: No XP?

 

Hello Helmut

I tried to install LTspice XVII on Vista 32b machine.

I could't succeed.
On LT web site, we can see LTXVII for Windows 7, 8 and 10.

Regards
PhB
Re: LTspice IV (NOT RESPONDING)

 

Hello Andy

"? If I turn on Mark Data Points ....."

I have the same thing and also with with long simulation using step param. .
I sometimes use the .save command

Regards
PhB
Re: No XP?

 

?I have Windows version 1.? Do you think LTspice works with it?? Should I blast someone at LTC for daring to come up with a program that doesn't?? Does this mean that LTC beats the dust? (or did you mean bites the dust? he-he) ?And, as you imply, does this mean LTC didn't ever do any engineering?

And what about Windows 3.1?? Are you still running it?? Do all your latest programs run on it?

Heck, does it irk you that LTspice -- any version -- isn't compatible with DOS 2.11?

Andy

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Re: No XP?

 

Hello,

I don't know about whether LTspiceXVII works with Vista, but it may work too.
Have you tested LTspiceXVII with Vista?

>?you will have to pay for it!

I am sure LTspice will be for free forever.

Best regards,
Helmut
Re: Sub circuit heat dissipation not showing

 

Thanks John for correcting me. I should have said Average Power. ?
No XP?

[email protected]
 

But whatabout vista?

I do not know about you guys, but I hate to putz around with computers. These are just tools, hammers so to speak, and I expect them to behave as such.

For your general knowledge? ALL 16 of my computers are still running

VISTA. I have invested too much in my software tools, money,time to understand and so on

to go out on a whim of some marketing guy that prompts me to upgrade to his last contraption.

Been there, done that!


And now comes LTC (or shell I say ANALOG) with a new, 'improved" version of heir otherwise

decent simulator.


And Guess what! It does not find it's own files!? HALAL as one of my friends said :)


And so, one more company,LTC, beats the dust. A pity.there is noplace any more for engineering.

Just Marketing, Marinating, MARKETING.


And hold on to your hats jents. Very soon, to add insult to injury, you will have to pay for it!


G.



G.
Re: Need help to design a transimpedance amplifier

 

I read through a few post, you want to detect from 200nA to 100uA with BW>=1MHz. You can do it in one single stage with feedback resistor of 50K. The output range is from 10mV to 5V. This is not hard to do. I uploaded the circuit and simulation using capacitance of APD of 5pF to show you get 1MHz BW.

I wrote my own excel program to calculate total noise. The numbers are for LTC6268, but if you go to the bottom, I have numbers for quite a few opamps you can plug into for noise simulation. I have short explanation how I calculate noise. I am not going to go through that in detail as this is LTSpice forum. Google and you'll find many article how to calculate noise of TIA. You can compare with my short explanation in the excel file. read through the instruction if you care to use the program for other opamps.

Good Luck.
Re: RC circuit time delay value not correct

 

Reminder:

When you joined this group, you read the instructions saying that pictures of schematics are not helpful, and should not be sent as a replacement for the schematic itself. ?It was particularly not helpful in this case because we had no idea that you uploaded a picture.

But the reminder remains: Upload your schematic file. ?Not a picture of it.

(OK, no need to in this case, because I already answered your question.)

Andy
Re: RC circuit time delay value not correct

 

wikihanya wrote:

? ?"... since the RC value is 100ps. it should introduce a delay of 100 ps ..."

That was your mistake.? An RC network has a frequency-dependent delay,?not a constant delay.

For the situation you described, the phase delay would be 32.14?degrees at 1 GHz, or 89.3 ps.

My LTspice simulation is in substantial agreement with that.

Regards,
Andy
Re: RC circuit time delay value not correct

 

wikihanya wrote:

"... since the RC value is 100ps. it should introduce a delay of 100 ps ..."

That was your mistake. An RC network has a frequency-dependent delay,
not a constant delay.

For the situation you described, the phase delay would be 32.14
degrees at 1 GHz, or 89.3 ps.

My LTspice simulation is in substantial agreement with that.

Regards,
Andy
Re: Henry's current transformer problem

John Woodgate
 

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For some ferrites, the Curie temperature, at which Br falls to zero, is not far above 100 degrees C.

?

With best wishes DESIGN IT IN! OOO ¨C Own Opinions Only

J M Woodgate and Associates Rayleigh England

?

Sylvae in aeternum manent.

?

From: LTspice@... [mailto:LTspice@...]
Sent: Friday, August 5, 2016 2:09 PM
To: LTspice@...
Subject: Re: [LTspice] Re: Henry's current transformer problem

?

?

From the available data we have not seen Br depending temperature change from 25¡ã C to 100¡ã C.

Bordodynov.

05.08.2016, 15:56, "hkafeman@... [LTspice]" <ltspice@...>:
> Borodoynov
>
> Thank you that looks like a good typical material to use.
>
> My understanding is then that given that I am operating at only 50Hz with just some high frequency transients, that any core losses will be insignificant.
>
> Then I can model in LTSpice the effects of ambient temperature using e.g.:
>
> Hc = 22 at 25C decreasing by 0.12 % per C
> Bs = 490m at 25C decreasing by 0.27 % per C
> Br = 100m at 25C - Does this have a temperature coefficient?
>
> Thanks and Regards
> Henry Kafeman
>
>

Re: RC circuit time delay value not correct

 

An RC filter does not 'delay' signals, but low pass filters them, with a frequency dependent phase delay. An RC value of 100ps says that the step response gets to 1/e of the final value in 100ps.

On 8/5/16 10:05 PM, wikihanya@... [LTspice] wrote:

Hi, i am new to LTSPICE. i am simulating this series RC circuit with an input of 1GHz. sine wave. since the RC value is 100ps. it should introduce a delay of 100 ps to the voltage across the capacitor but the LTSPICE shows a time difference of only 91ps, why is that? . thanks

--
Richard Damon
Re: RC circuit time delay value not correct

John Woodgate
 

¿ªÔÆÌåÓý

We don't know, because you have not uploaded your .asc file to Files => Temp on the list's web site. When you have done that, we can run it to compare our results.

?

Even in this apparently simple case, uploading the .asc file is valuable.

?

With best wishes DESIGN IT IN! OOO ¨C Own Opinions Only

J M Woodgate and Associates Rayleigh England

?

Sylvae in aeternum manent.

?

From: LTspice@... [mailto:LTspice@...]
Sent: Saturday, August 6, 2016 3:05 AM
To: LTspice@...
Subject: [LTspice] RC circuit time delay value not correct

?

?

Hi, i am new to LTSPICE. i am simulating this series RC circuit with an input of 1GHz. sine wave. since the RC value is 100ps. it should introduce a delay of 100 ps to the voltage across the capacitor but the LTSPICE shows a time difference of only 91ps, why is that? . thanks
Re: RC circuit time delay value not correct

 

Hello 4cwnirjjs53rhghqimgmcb5zflk7qn7mkdjgphlk

We can't see the screen of your computer.

Please upload your example in the section Files\temp of this group.

Regards
PhB
RC circuit time delay value not correct

 

Hi, i am new to LTSPICE. i am simulating this series RC circuit with an input of 1GHz. sine wave. since the RC value is 100ps. it should introduce a delay of 100 ps to the voltage across the capacitor but the LTSPICE shows a time difference of only 91ps, why is that? . thanks
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