On 20/08/2021 16:11, jlarkin@highlandsniptechnology.com wrote:> On Fri, 20 Aug 2021 11:41:30 +0100, Clive Arthur > <clive@nowaytoday.co.uk> wrote: > >> On 20/08/2021 00:08, John Larkin wrote: >>> Suppose I have a circuit with 20 nodes, N1 ... N20. >>> >>> I want to plot the node voltages, left to right on the screen. >>> >>> Any ideas? >>> >>> Clumsy ways: >>> >>> Build an analog mux and clock it with a counter, plot with time as >>> x-axis >>> >>> Push a pulse into a tapped transmission line to sequence a bunch of >>> switches >>> >>> Export a file and do it in a separate program >>> >> >> Shift register from D flops plus analog switches. > > Yes, but a few analog mux's and a counter is less busy. I just noticed > that LT Spice now includes the ADI analog mux chips. > > Six pulse generator voltage sources would generate the addresses and > enables for three 8:1 mux chips. I guess one could use the LT counter > element as a ripple counter too... 4 of those.Switches with a .model can be made (almost) perfect. One less thing to worry about. -- Cheers Clive
LT Spice challenge
Started by ●August 19, 2021
Reply by ●August 20, 20212021-08-20
Reply by ●August 20, 20212021-08-20
jlarkin@highlandsniptechnology.com wrote:> On Fri, 20 Aug 2021 09:57:26 -0000 (UTC), Steve Wilson > <spamme@not.com> wrote:[...]>>> I want a plot. >>> >>> LT Spice now has the ADG1208 analog mux. Three of them lets me scan 24 >>> points. I can drive them from a 1 Hz counter or a few pulse generators. >> >>You can also decode the .RAW file and do anything you want with the data. > > Sure, but that's a chore and isn't very interactive. People (and mice) > learn from rapid feedback.OK, but keep it in mind when you need to do some curve fitting, especially to noisy data. -- The best designs occur in the theta state. - sw
Reply by ●August 20, 20212021-08-20
On Fri, 20 Aug 2021 16:03:21 -0000 (UTC), Steve Wilson <spamme@not.com> wrote:>jlarkin@highlandsniptechnology.com wrote: > >> On Fri, 20 Aug 2021 09:57:26 -0000 (UTC), Steve Wilson >> <spamme@not.com> wrote: > >[...] > >>>> I want a plot. >>>> >>>> LT Spice now has the ADG1208 analog mux. Three of them lets me scan 24 >>>> points. I can drive them from a 1 Hz counter or a few pulse generators. >>> >>>You can also decode the .RAW file and do anything you want with the data. >> >> Sure, but that's a chore and isn't very interactive. People (and mice) >> learn from rapid feedback. > >OK, but keep it in mind when you need to do some curve fitting, especially to >noisy data. >I like to stay inside Spice when I can. As in adding a lowpass filter for looking at wideband data. My current case would have no noise. Spice doesn't do time-domain noise. Mike E says that the true value of Spice is for training your instincts. That works best with rapid visual shape-based feedback. -- Father Brown's figure remained quite dark and still; but in that instant he had lost his head. His head was always most valuable when he had lost it.
Reply by ●August 20, 20212021-08-20
On 20/08/2021 16:28, Clive Arthur wrote:> On 20/08/2021 16:11, jlarkin@highlandsniptechnology.com wrote: >> On Fri, 20 Aug 2021 11:41:30 +0100, Clive Arthur >> <clive@nowaytoday.co.uk> wrote: >> >>> On 20/08/2021 00:08, John Larkin wrote: >>>> Suppose I have a circuit with 20 nodes, N1 ... N20. >>>> >>>> I want to plot the node voltages, left to right on the screen. >>>> >>>> Any ideas? >>>> >>>> Clumsy ways: >>>> >>>> Build an analog mux and clock it with a counter, plot with time as >>>> x-axis >>>> >>>> Push a pulse into a tapped transmission line to sequence a bunch of >>>> switches >>>> >>>> Export a file and do it in a separate program >>>> >>> >>> Shift register from D flops plus analog switches. >> >> Yes, but a few analog mux's and a counter is less busy. I just noticed >> that LT Spice now includes the ADI analog mux chips. >> >> Six pulse generator voltage sources would generate the addresses and >> enables for three 8:1 mux chips. I guess one could use the LT counter >> element as a ripple counter too... 4 of those. > > Switches with a .model can be made (almost) perfect. One less thing to > worry about. >And each switch operated with its own delayed pulse voltage source... PULSE(0 5 {1*Td} 1u 1u 1m) PULSE(0 5 {2*Td} 1u 1u 1m) PULSE(0 5 {3*Td} 1u 1u 1m) etc -- Cheers Clive
Reply by ●August 20, 20212021-08-20
jlarkin@highlandsniptechnology.com wrote:> On Fri, 20 Aug 2021 16:03:21 -0000 (UTC), Steve Wilson > <spamme@not.com> wrote: > >>jlarkin@highlandsniptechnology.com wrote: >> >>> On Fri, 20 Aug 2021 09:57:26 -0000 (UTC), Steve Wilson >>> <spamme@not.com> wrote: >> >>[...] >> >>>>> I want a plot. >>>>> >>>>> LT Spice now has the ADG1208 analog mux. Three of them lets me scan >>>>> 24 points. I can drive them from a 1 Hz counter or a few pulse >>>>> generators. >>>> >>>>You can also decode the .RAW file and do anything you want with the >>>>data. >>> >>> Sure, but that's a chore and isn't very interactive. People (and mice) >>> learn from rapid feedback. >> >>OK, but keep it in mind when you need to do some curve fitting, >>especially to noisy data. >> > > I like to stay inside Spice when I can. As in adding a lowpass filter > for looking at wideband data. My current case would have no noise. > Spice doesn't do time-domain noise.Sure it does. You can use Box-Mueller. You can also add shot noise, as in optical transimpedance amplifiers. I'd post the ASC files, but they will suffer from word wrap in the text portions and never load. I'd zip them up and post to google drive, but that is turning out to be a real pain. I just got my own website at https://www.namecheap.com/, but I was having problems linking to their nameservers in Filezilla. They sent me an email giving all the directions, but I haven't had time to implement them yet. Soon...> Mike E says that the true value of Spice is for training your > instincts. That works best with rapid visual shape-based feedback.I agree. I am still amazed that one man can write such a powerful program. Have you ever been to one of his seminars? Absolutely amazing! I still have the T-shirt, but I washed it in a load of laundry using bleach, and it turned pink so I can't wear it. But I keep it as a memento. -- The best designs occur in the theta state. - sw
Reply by ●August 20, 20212021-08-20
On Thursday, August 19, 2021 at 11:08:23 PM UTC, John Larkin wrote:> Suppose I have a circuit with 20 nodes, N1 ... N20. > > I want to plot the node voltages, left to right on the screen. > > Any ideas? > > Clumsy ways: > > Build an analog mux and clock it with a counter, plot with time as > x-axis > > Push a pulse into a tapped transmission line to sequence a bunch of > switches > > Export a file and do it in a separate programHello John, So the issue is LTSpice won't plot that many (n=20) in one graph? Sorry, I use MicroCap, not LTSPice. Plotting 20 nodes is no sweat in MicroCap. Or, you want 20 separate plots, each in its own window? That, I can't do either. In any case, I would export* the data & graph it in Excel. *In MicroCap: Run Transient Analysis (Alt-1). F10 > Numeric Output > Check All, Data Points=Actual, "OK" Re-run Transient Analysis (F2), see Numeric Output (F5) cheers, RS
Reply by ●August 20, 20212021-08-20
Steve Wilson wrote:> jlarkin@highlandsniptechnology.com wrote: > >> On Fri, 20 Aug 2021 16:03:21 -0000 (UTC), Steve Wilson >> <spamme@not.com> wrote: >> >>> jlarkin@highlandsniptechnology.com wrote: >>> >>>> On Fri, 20 Aug 2021 09:57:26 -0000 (UTC), Steve Wilson >>>> <spamme@not.com> wrote: >>> >>> [...] >>> >>>>>> I want a plot. >>>>>> >>>>>> LT Spice now has the ADG1208 analog mux. Three of them lets me scan >>>>>> 24 points. I can drive them from a 1 Hz counter or a few pulse >>>>>> generators. >>>>> >>>>> You can also decode the .RAW file and do anything you want with the >>>>> data. >>>> >>>> Sure, but that's a chore and isn't very interactive. People (and mice) >>>> learn from rapid feedback. >>> >>> OK, but keep it in mind when you need to do some curve fitting, >>> especially to noisy data. >>> >> >> I like to stay inside Spice when I can. As in adding a lowpass filter >> for looking at wideband data. My current case would have no noise. >> Spice doesn't do time-domain noise. > > Sure it does. You can use Box-Mueller.One approach is to use another program (probably using the BM algorithm under the covers) to generate .wav files and using those. They can be summed together with different delays to generate new instances of the random noise. You can also add shot noise, as in> optical transimpedance amplifiers.Only in .noise simulations, and it's non-obvious. I got it working once but then just bailed out because the math is so simple anyway.> > I'd post the ASC files, but they will suffer from word wrap in the text > portions and never load. I'd zip them up and post to google drive, but that > is turning out to be a real pain. I just got my own website at > https://www.namecheap.com/, but I was having problems linking to their > nameservers in Filezilla. They sent me an email giving all the directions, > but I haven't had time to implement them yet. Soon...> >> Mike E says that the true value of Spice is for training your >> instincts. That works best with rapid visual shape-based feedback. > > I agree. I am still amazed that one man can write such a powerful program. > Have you ever been to one of his seminars? Absolutely amazing! I still have > the T-shirt, but I washed it in a load of laundry using bleach, and it > turned pink so I can't wear it. But I keep it as a memento.Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
Reply by ●August 20, 20212021-08-20
On Fri, 20 Aug 2021 10:16:05 -0700 (PDT), Rich S <richsulinengineer@gmail.com> wrote:>On Thursday, August 19, 2021 at 11:08:23 PM UTC, John Larkin wrote: >> Suppose I have a circuit with 20 nodes, N1 ... N20. >> >> I want to plot the node voltages, left to right on the screen. >> >> Any ideas? >> >> Clumsy ways: >> >> Build an analog mux and clock it with a counter, plot with time as >> x-axis >> >> Push a pulse into a tapped transmission line to sequence a bunch of >> switches >> >> Export a file and do it in a separate program > >Hello John, >So the issue is LTSpice won't plot that many (n=20) in one graph?No. I want a screen where X-axis is node number and Y axis is the voltage on each node, left to right. That graphs a voltage trend line along a row of nodes. Looks like a time-stepped analog mux is the best (only?) way to do that. -- Father Brown's figure remained quite dark and still; but in that instant he had lost his head. His head was always most valuable when he had lost it.
Reply by ●August 20, 20212021-08-20
On Fri, 20 Aug 2021 16:55:14 -0000 (UTC), Steve Wilson <spamme@not.com> wrote:>jlarkin@highlandsniptechnology.com wrote: > >> On Fri, 20 Aug 2021 16:03:21 -0000 (UTC), Steve Wilson >> <spamme@not.com> wrote: >> >>>jlarkin@highlandsniptechnology.com wrote: >>> >>>> On Fri, 20 Aug 2021 09:57:26 -0000 (UTC), Steve Wilson >>>> <spamme@not.com> wrote: >>> >>>[...] >>> >>>>>> I want a plot. >>>>>> >>>>>> LT Spice now has the ADG1208 analog mux. Three of them lets me scan >>>>>> 24 points. I can drive them from a 1 Hz counter or a few pulse >>>>>> generators. >>>>> >>>>>You can also decode the .RAW file and do anything you want with the >>>>>data. >>>> >>>> Sure, but that's a chore and isn't very interactive. People (and mice) >>>> learn from rapid feedback. >>> >>>OK, but keep it in mind when you need to do some curve fitting, >>>especially to noisy data. >>> >> >> I like to stay inside Spice when I can. As in adding a lowpass filter >> for looking at wideband data. My current case would have no noise. >> Spice doesn't do time-domain noise. > >Sure it does. You can use Box-Mueller. You can also add shot noise, as in >optical transimpedance amplifiers.Sure, you can make time-domain noise sources and add them into a circuit, but that is a real nuisance when you need a lot of them. I've used the Spice random functions.> >I'd post the ASC files, but they will suffer from word wrap in the text >portions and never load. I'd zip them up and post to google drive, but that >is turning out to be a real pain. I just got my own website at >https://www.namecheap.com/, but I was having problems linking to their >nameservers in Filezilla. They sent me an email giving all the directions, >but I haven't had time to implement them yet. Soon... > >> Mike E says that the true value of Spice is for training your >> instincts. That works best with rapid visual shape-based feedback. > >I agree. I am still amazed that one man can write such a powerful program. >Have you ever been to one of his seminars? Absolutely amazing! I still have >the T-shirt, but I washed it in a load of laundry using bleach, and it >turned pink so I can't wear it. But I keep it as a memento. > >One of my guys attended and learned a lot of tricks. -- Father Brown's figure remained quite dark and still; but in that instant he had lost his head. His head was always most valuable when he had lost it.
Reply by ●August 20, 20212021-08-20
jlarkin@highlandsniptechnology.com wrote:> On Fri, 20 Aug 2021 16:55:14 -0000 (UTC), Steve Wilson > <spamme@not.com> wrote: > >> jlarkin@highlandsniptechnology.com wrote: >> >>> On Fri, 20 Aug 2021 16:03:21 -0000 (UTC), Steve Wilson >>> <spamme@not.com> wrote: >>> >>>> jlarkin@highlandsniptechnology.com wrote: >>>> >>>>> On Fri, 20 Aug 2021 09:57:26 -0000 (UTC), Steve Wilson >>>>> <spamme@not.com> wrote: >>>> >>>> [...] >>>> >>>>>>> I want a plot. >>>>>>> >>>>>>> LT Spice now has the ADG1208 analog mux. Three of them lets me scan >>>>>>> 24 points. I can drive them from a 1 Hz counter or a few pulse >>>>>>> generators. >>>>>> >>>>>> You can also decode the .RAW file and do anything you want with the >>>>>> data. >>>>> >>>>> Sure, but that's a chore and isn't very interactive. People (and mice) >>>>> learn from rapid feedback. >>>> >>>> OK, but keep it in mind when you need to do some curve fitting, >>>> especially to noisy data. >>>> >>> >>> I like to stay inside Spice when I can. As in adding a lowpass filter >>> for looking at wideband data. My current case would have no noise. >>> Spice doesn't do time-domain noise. >> >> Sure it does. You can use Box-Mueller. You can also add shot noise, as in >> optical transimpedance amplifiers. > > Sure, you can make time-domain noise sources and add them into a > circuit, but that is a real nuisance when you need a lot of them. > > I've used the Spice random functions. > >> >> I'd post the ASC files, but they will suffer from word wrap in the text >> portions and never load. I'd zip them up and post to google drive, but that >> is turning out to be a real pain. I just got my own website at >> https://www.namecheap.com/, but I was having problems linking to their >> nameservers in Filezilla. They sent me an email giving all the directions, >> but I haven't had time to implement them yet. Soon... >> >>> Mike E says that the true value of Spice is for training your >>> instincts. That works best with rapid visual shape-based feedback. >> >> I agree. I am still amazed that one man can write such a powerful program. >> Have you ever been to one of his seminars? Absolutely amazing! I still have >> the T-shirt, but I washed it in a load of laundry using bleach, and it >> turned pink so I can't wear it. But I keep it as a memento. >> >> > > One of my guys attended and learned a lot of tricks.I went to one 15 or so years back. Not a bad use of a day. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net http://hobbs-eo.com
