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Re: LTspice XVII Co-exist with LTspice IV?
Jim wrote: ? ?"Are LTspice XVII schematics still *.asc?? If so, which program ? ? version do you assign as "Open with"?" ?Both versions of LTspice are essentially the same thing (aside from many not-so-minor differences between them!).? They are both LTspice.? They use exactly the same input files and output files.? It's just that, in operation, one of them is more advanced than the other.? And it has a FEW new devices that the other one doesn't have, but that doesn't matter unless you use those devices. Whichever program you installed last, would be the one that automatically opens when you double-click on a schematic file. You can change those assignments, of course.? It would be your preference, which one you want to open. Andy |
Re: I'm ready to give up LTC all toghether.
Replying to a few specific questions from Gunoi Nare: ? ?"However, I was looking for a definition of Trise etc. that really does not exist in the help file.." Well, it does.? In the Help page for A-devices, "Trise" etc. are in the table of parameters. ? ?"From what level to what level is the simulator considering the rise of a signal?" I think it is from 0% to 100%.? But your results may vary, depending on the Maximum Timestep of the simulation, as well as waveform compression (whether you have ".options plotwinsize=0"). ? ?"Is Trise a .parameter , a key word or what?. How do you handle it' s substitutions." Trise can be both, which can make it confusing if you don't keep them straight. As you used it, Trise was a USER-defined parameter and has meaning only to you. When you attach "Trise=5ns" to a NAND gate, it is an instance parameter of that NAND gate. When you attach "Trise={foo}" to a NAND gate, the user-defined parameter "foo" is substituted with its numeric value, which is then assigned to the instance parameter "Trise". When you attach "Trise={Trise}" to the NAND gate, the user-defined parameter "Trise" is substituted with its numeric value, which is then assigned to the instance parameter "Trise".? This "Trise" is totally different than your user-defined parameter by the same name. ? ?"BTW. If you leave unused pins of the gate just floating, how do you simulate latch-up conditions?" You were using the built-in NAND gate which is an A-device, and is not a real gate.? It has no transistors.? It has no latch-up, and no problem with inputs floating.? In fact, floating inputs are preferred, if you don't actually use them. If you want to simulate latch-up, you would have to come up with a real circuit for your own NAND gate. Regards, Andy |
Re: I'm ready to give up LTC all toghether.
Gunoi Nare, let me offer my "take" on this. LTspice's A-devices like the one you used, originally were for LTC's internal use only and not documented at all.? Then Mike made them available for anyone to use and provided minimal documentation, in the Help page for them ("A. Special Functions"). As most of us here in this group know and occasionally discuss, LTspice's Help documentation is and has always been short on details.? We are OK with that because the program that comes with it, is so incredible.? The Help file alone really is not a good way to go from the ground up, to having a solid understanding of how to use LTspice, or SPICE in general.? There are other resources that help fill in the missing pieces.? But there also is a general understanding (partly learned from experience) about how SPICE/LTspice work, which might have prevented this problem that you had. I think you are correct that many of the Symbols that come built into LTspice, ought to have some parameters already attached to them, so that we don't have to always dig up the documentation or remember which ones we need to add.? That is especially true about the A-devices.? For example, I occasionally use the Modulate (VCO) component, and it doesn't work without the parameters Mark and Space -- so why doesn't LTspice have those two already attached to the symbol before I ever use it?? It's a good question, with no real answer.? That's just the way it is. ?(I suppose Mike might say that the standard library is "clean" with no parameters attached, because attaching parameters is the job of the user, or something like that.) However, you can edit those symbols!? Just open them in LTspice and attach the parameters yourself, and save them -- ASSUMING that Windows lets you! ?(It might not, if you installed LTspice in the Windows "Program Files" area.) ?Then they will be attached already whenever you use that symbol. ?(This answers your question,?"Is there a way for me to modify the lib so the components would have already some dummy values?") ?I'm not sure if they will last through an LTspice program update, but that's a separate issue. Now, let's examine why your schematic didn't work. You defined .PARAMs which you named TRISE and THIGH, and then used them within {braces}.? Using braces converts the user-defined .PARAMs into pure numbers.? So your NAND gate, A1, had the parameters 5.0e-9 and 3.0 attached to it -- but with nothing telling the SPICE engine (internal to LTspice) what they are for.? Think of it this way.? The schematic editor says that you have a NAND gate, with parameters 0.000000005 and 3.0.? And that's all it says.? Once those user-defined .PARAMs have been converted into numbers, everything downstream doesn't know that you named them TRISE or ELEPHANT. Even if the SPICE engine knew that you named them "TRISE" and "THIGH", it wouldn't help, because user-defined .PARAMs have names that are meaningful only to YOU.? LTspice doesn't (for the most part) care what names you use, and doesn't interpret them. User-defined .PARAM names are your private names. The NAND gate needs those values given to it as "name=number" pairs.? It needs to see "Trise=5ns" or "Trise=0.000000005" or "Trise={trise}" or "Trise={elephant}.? Otherwise, it doesn't know what to do with the number. This can be confusing, because SPICE is not 100% consistent about that.? With a resistor, you can use just the resistance value (a number), without having to say "Res=470".? But that pretty much only works with the things that SPICE (40+ years ago) defined that way.? Most other parameters need to have the "name=number" form, when they appear on the device that uses them. Here's a tip.? In SPICE, if a number must be used in a particular order, then probably it is used as a number alone. ?(Examples: the .TRAN statement, or the PULSE voltage source.) ?If the order doesn't matter, then it must always be used in "name=number" form. ?(Examples: all the values of a .MODEL statement, and all parameters attached to A- and B-elements.) Andy |
Re: Visay spice model Bridge rectifier KBU6B
You will have to construct the bridge from 4 discrete diodes, for which you can use this:
.MODEL GBU6J D + IS=1.528E-12 + N=1.00 + RS=1.800E-3 + IKF=1.85E-3 + CJO=5.15E-10 + M=0.408 + VJ=0.75 + ISR=4.50E-6 + BV=618 + IBV=2.50E-3 + TBV1=4.2E-7 This model is from Fairchild. The GBU6J is an equivalent device. Regards, Tony |
Re: LTspice XVII Co-exist with LTspice IV?
Hello JIm
You wrote : " Are LTspice XVII schematics still *.asc? If so, which program version do you assign as "Open with"? " I am surprised that YOU, a long user of LTspice ,? ask for such a question. Why don't you try ? 1/ For sure schematics are still .asc 2/ There is a problem with windows to assign multiple versions od LTspice? (IV or XVII) with the fonction "Open with" of Windows. Perhaps ask to M. Enguelhart Maybe I have not well understood ypur question. Best Regards PhB |
Re: Visay optocoupler
pietervanpoecke?wrote: ? ?"I'am searching for the spice model of the visay optocoupler SFH 618A-2 and SFH618A-4. Can somebody help me?" I don't know if this helps.? I did a quick search but didn't find one.? However, Vishay has SPICE models for parts with similar part numbers: SFH615A and SFH617A.? I don't know what is different between these and the SFH618A, and whether you can adapt one of them to it. ?(Sometimes one gets real lucky and two part numbers are actually the same device in a different package.) You might also try asking Vishay if they have the model for your part already. By the way, it is "Vishay", not "visay". Andy |
Re: LTspice XVII Co-exist with LTspice IV?
At 07:08 AM (-0700) 8/15/2016, Helmut Sennewald wrote:
---------- Original Message ---------- Hello Jim,---------- End of Original Message ---------- Are LTspice XVII schematics still *.asc? If so, which program version do you assign as "Open with"? ...Jim Thompson Web Site: <> |
Re: MAC - Software Update Seems To Fail
Helmut,
Thank-You for taking the time to confirm the behavior experienced with the software update. Now, at least, other Mac users can see this topic and know that they are not alone if this issue is encountered.? I'll send an e-mail to Mike to inform him of the problem. Regards, -jack |
Re: MAC - Software Update Seems To Fail
John Woodgate
¿ªÔÆÌåÓýWell, it might have worked. (Saddest sentence that exists!). So now I agree with Helmut; report the issue to Mike E. ? 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: Monday, August 15, 2016 4:05 PM To: LTspice@... Subject: RE: [LTspice] MAC - Software Update Seems To Fail ? ? Hi John, ? Thank-You for the reply, but (re) downloading from the official site and reinstalling does not work either. ? Please note that this is the Mac OS version. ? -jack ? |
Re: MAC - Software Update Seems To Fail
Hello Jack,
I just tested your case. Indeed MAC-LTspice always reports "not updated since 126 days". The reason for that seems to be that the last version has been from Apr 11 2016. One will get a similar message on LTspiceIV when not updated for more than 100? days. I updated now MAC-LTspice on my MAC and checked for the latest added part LT8335. It"s in the library now. This means all the models are up to date after the update. I recommend to regularly update to get the latest models. I guess it"s the first time that there were so long no program update for MAC-LTspice. I wouldn't worry about this message. Nevertheless you could write a message to Mike, the author of LTspice - LTspice@.... I am not sure he can quickly fix this due to the actual work on LTspiceXVII. Best regards, Helmut |
Re: MAC - Software Update Seems To Fail
John Woodgate
¿ªÔÆÌåÓýUninstall it and re-install a download from the official LT web site. ? 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: Monday, August 15, 2016 3:21 PM To: LTspice@... Subject: [LTspice] MAC - Software Update Seems To Fail ? ? Starting Saturday (08/13), every time LTspice is started it continually requests that a software update be performed despite having already attempted the operation several times. Seems like either the internal URL used for the request does not have the latest version; or, some internal status is not being set when the new version is installed. Please note that the model updates appear to work properly. ? Any/all help is appreciated. ? Thank-You, -jack ? ? |
Re: I'm ready to give up LTC all toghether.
At 07:08 AM (-0700) 8/15/2016, davnor49 wrote:
---------- Original Message ---------- G,---------- End of Original Message ---------- Yep. I amuse myself periodically by remembering that I designed ASIC's for 18 years before I had my hands on a simulator, and that was Berkeley Spice 2G6 on a VAX. And there was no schematic capture... I had to draw schematics on paper, number the nodes, then type up a netlist :-D In a way I think that's an advantage... I design circuits in my head, on paper, and with a calculator, then enter them into a simulator for verification. I find that many young engineers have no ability to IMAGINE a circuit. ...Jim Thompson Web Site: <> |
MAC - Software Update Seems To Fail
Starting Saturday (08/13), every time LTspice is started it continually requests that a software update be performed despite having already attempted the operation several times. Seems like either the internal URL used for the request does not have the latest version; or, some internal status is not being set when the new version is installed. Please note that the model updates appear to work properly. Any/all help is appreciated. Thank-You, -jack |
Re: LTspice XVII Co-exist with LTspice IV?
On my home computer has these two programs. True, I set XVII to drive D :. I run any program. There is no conflict.
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Bordodynov. 15.08.2016, 16:31, "Jim Thompson ltlist@... [LTspice]" <ltspice@...>: Can LTspice XVII Co-exist with LTspice IV on the same machine without |