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Re: No XP?
?? Many Linux users dual-boot with Windows for the few Windows programs? without Linux equivalents (Intuit, I'm talking to you). Maybe someone who's locked into XP could try dual-booting with Linux to run LTspice and let us know how it goes. ?? Craig On Aug 7, 2016 5:23 PM, "Richard Damon richard@... [LTspice]" <LTspice@...> wrote:
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Re: No XP?
On 8/7/16 4:56 PM, ricksbmw@... [LTspice] wrote:
While I can't speak for Mike, I can say that often such restrictions are based on the tools used to build the program. Since XP is (past) EOL, many tools don't support generating new programs for it. Since LTSpiceVII is avail for 64 bits, it likely is using a newer tool than LTSpiceIV, and that might not support XP. -- Richard Damon |
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Re: No XP?
John Woodgate
¿ªÔÆÌåÓýSurely LTspice IV runs on XP and will continue to do so. As I understand it, the new graphics engine in XVII doesn't work on those legacy versions of Windows, which is hardly a surprise. ? 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: Sunday, August 7, 2016 9:57 PM To: LTspice@... Subject: [LTspice] Re: No XP? ? ? It would seem reasonable for Mike to provide a short explanation of the technical reasons for not providing compatibility with XP (would it have been that costly?). |
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Re: No XP?
It would seem reasonable for Mike to provide a short explanation of the
technical reasons for not providing compatibility with XP (would it have
been that costly?).
A significant part of the world still runs XP because the economics of replacing perfectly good hardware with something that will support 7,8, or 10. It is not a trivial expense for a good part of the world, and detractors? don't seem to understand that. Rick |
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Re: Sub circuit heat dissipation not showing
Helmut wrote: ? ?"I have again problems with delayed or not delivered messages." It's not only your problem.? Yahoo is being hammered with problems this last week.? Those long delays are showing up all over. ? ?"Ctrl left mouse click on the plot formula in the waveform viewer.? ? ? LTspice will then show a small window with the average power." I think the confusion came up because LTspice displays a number for power dissipation, in the lower left corner of your LTspice screen, by just hovering the mouse pointer over a component and not clicking anything.? But that number is the power dissipation ONLY at time=0 into the simulation, and doesn't represent average power over a full cycle. The other confusion (which started this whole thread) is that LTspice doesn't show the power in the lower left corner, when the component is a subcircuit.? I guess that's just the way LTspice works; there is something about subckt models that makes that calculation not happen.? But for me, that number is not helpful anyway, even if it was there. Andy |
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Re: Current Dependent Voltage Source
Thanks to everyone who expertly explained how to accomplish this.? With all your help I was able to get my simulation to work?using the table of test data I collected.?? Thank you for helping me.? Sent from Yahoo Mail. On Thursday, August 4, 2016 8:31 AM, "Andy ai.egrps@... [LTspice]" wrote:
?
" ? rmoreno.phone" asked how to enter a table of measured values for her/his CCVS.Vlad might have had the table descriptions a little bit confused with respect to your question, because I think the data you have is voltage/current values, not voltage/time values.? You wanted a controlled or dependent source, not an independent source. Using SPICE's built-in H element (current controlled voltage source or CCVS), LTspice *MIGHT* have the ability to accept a table of current/voltage values.? See the Help pages for E (VCVS) and G (VCCS) elements.? A table is listed as an option. ?"A look-up table is used to specify the transfer function." ?The same 'table' description is not listed for the F (CCCS) and H (CCVS) elements.? I am not sure if that was an omission on those Help pages, or if that option really doesn't exist for those two controlled sources.? The "LTwiki" () is where I usually go when I have questions about the Help pages.? Unfortunately, the LTwiki also doesn't show a table option for the CCVS.? That leads me to believe that you can't use a table with the standard CCVS element. But LTspice's B-elements can do that and much more. Here is from the Help page for B-elements: ? table(x,a,b,c,d,...) ??Interpolate a value for x based on a look up table given as a set of pairs of
points. Start with a Bv symbol, then right-click on "V=F(...)" and edit it.? I think (but could be wrong) it should look like this when you are done: V=Table( I(V4), 0mA, 0V, 1mA, 1mV, 2mA, 1.9mV, 3mA, 2.5mV ...) where I(V4) means the current measured through V4 (this is your controlling current), and the pairs that come next, are the (current, voltage) pairs that you measured. I have rarely used the Table() functions in LTspice, so please excuse my inexperience with them. Regards, Andy |
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Re: Need help to design a transimpedance amplifier
How come it took two days before my message were posted?
You look for an opamp, it's not the bias current you worry because you are only measuring 200nA lowest. Any opamp with bias current less than 10nA is plenty good. The most important thing you look for is input capacitance. Most of the opamps have over 5pF of input capacitance and that will increase the noise gain. You want to understand noise gain, read the explanation in my Excel file. I explain each and every component of the noise source and the relevant frequency range. I chose LTC6268 because the input capacitance is about 0.5pF. For your requirement, some BJT input opamp might be good enough, just look for low input capacitance. That said, you always see noise coupling into TIA circuits. I never saw a TIA circuit that dose not pick up all sort of noise.? All the noise calculation and the excel file I provided are ONLY for ideal theoretical noise limit. If you leave the bare circuit, you will see all the noise from around the surrounding. FYI, our contractor designed another TIA that has only a 1M feedback resistor and it pick up all sort of noise. We have to re-layout the board to put in the shield. A ground plane is an absolute MUST. The other reason is people have long trace at the -ve input. That will pickup noise every time. Layout is everything. This is beyond the scope of this forum. Circuit is always simple, it's the layout and shielding. You need to look at your layout, put in the shielding, then talk more about it. LTSpice is NOT the place to talk about this, go to some electronic forum and ask question. I feel I already way out of bound here already. You are only working with 50K feedback resistors. My circuit use 250M, and I designed with up to 2G resistors TIA circuits. Layout and shielding become the number one design. If you read my other post, 50K resistor will give you output range of 10mV to 5V( fit your 5V supply requirement). This is very easy signal to deal with. We deal with a lot lower signal successfully. |
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Re: PWL file in LTSPICE XVII not working while working in LT spice IV
Hi Helmut
But when I try to install the 64 bit version, it installs the 32 bit. Don't know why? I made it several times but keep? receiving the same bug. I did send a message to help address. It's really a pity: this software seemed flawless up tyo now. I think I 'm going to continue to use LT spice IV |
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Re: PWL file in LTSPICE XVII not working while working in LT spice IV
John Woodgate
¿ªÔÆÌåÓýOne for Mike E, I think. Report the effect to the first address you find in Help =>About LTspice. ? 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: Sunday, August 7, 2016 2:07 PM To: LTspice@... Subject: [LTspice] PWL file in LTSPICE XVII not working while working in LT spice IV ? ? Hello |
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Re: PWL file in LTSPICE XVII not working while working in LT spice IV
Hello,
This problem only happens with LTspiceXVII(x86), the 32 bit version. I have reported this problem more than two weeks ago. Please use the 64 bit version of LTspiceXVII. This version runs with PWL sources. Maybe you should also send a bug message to the email address given in the? Help->About of the program. Best regards, Helmut |
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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 |
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Re: Sub circuit heat dissipation not showing
John Woodgate
¿ªÔÆÌåÓýDepend 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'." ? 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. ? Andy ? ? |
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Re: Need help to design a transimpedance amplifier
¿ªÔÆÌåÓýWould 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?:
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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
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