74HC4046 Model Development

Started by Jim Thompson in sci.electronics.design10 years ago 23 replies

I have been notified by Helmut Sennewald that the LTspice encryption process hides the node sequence. So please...

I have been notified by Helmut Sennewald that the LTspice encryption process hides the node sequence. So please revisit... http://www.analog-innovations.com/SED/HC4046_SUB.zip for a corrected version. This is just the VCO portion for now, and just the variable part; suitable only for LTspice. Please try it out and let me know your comments, etc. Since I'm new to working with LTsp...


74HC74 oscillator simulation

Started by bitrex in sci.electronics.design3 years ago 36 replies

IRL I don't think there's anything this configuration of the 'HC74 could do but oscillate; with an RC network from not-Q to not-CLR and D, CLK,...

IRL I don't think there's anything this configuration of the 'HC74 could do but oscillate; with an RC network from not-Q to not-CLR and D, CLK, and not-PRE grounded. But with these models from the Yahoo LTSpice users group the LTSPice time domain looks like it manages to find some other metastable state and sits there spinning its wheels. Can anyone suggest some ICs that could bust i...


Variable inductor in LTSpice

Started by Piotr Wyderski in sci.electronics.design7 years ago 11 replies

How do I define a voltage (or current)-dependent inductor in LTSpice? In the case of a resistor I simply write R=100*V(Vkey), but the simulator...

How do I define a voltage (or current)-dependent inductor in LTSpice? In the case of a resistor I simply write R=100*V(Vkey), but the simulator refuses to accept L=... I don't care about hysteresis, pure reactance is all I want to simulate now. The non-linear effects need to wait. Bets regards, Piotr


LTSpice multicore usage

Started by bitrex in sci.electronics.design7 years ago

Does anyone have experience in how effectively LTSpice leverages multicore processors? Is it also architecture/processor specific? In the...

Does anyone have experience in how effectively LTSpice leverages multicore processors? Is it also architecture/processor specific? In the setup for a sim I can select how many cores I wish to devote to the simulation. I have a cheap Celeron netbook that I use when I'm out (the beater laptop) which has two cores (probably not the type of machine one should really be using, but it does ok...


Learning about oscillators in LTSpice

Started by Clifford Heath in sci.electronics.design8 years ago 68 replies

I'm just getting started with LTSpice, and played yesterday with some Colpitts oscillators to my satisfaction. Today I tried a Hartley, and I...

I'm just getting started with LTSpice, and played yesterday with some Colpitts oscillators to my satisfaction. Today I tried a Hartley, and I can't understand some of the behaviour I'm seeing. In the attached circuit, I've added an emitter resister in an attempt to reduce the high collector current. Merely increasing the base resistor didn't help until the oscillator stopped entirely. Act...


Finding LTspice Models

Started by Ricky C in sci.electronics.design3 years ago 13 replies

LTspice is a nice program... well, it's ok in many respects and great in others. But it can be a PITA to find models for. I'm looking at a...

LTspice is a nice program... well, it's ok in many respects and great in others. But it can be a PITA to find models for. I'm looking at a number of possible parts to use in a new design but many of them have no spice models. I'm not so worried about finding an accurate LED model. But I'm using a Schottky diode to prevent back feeding of power through a regulator and I need a


Can you run LTspice on a cellphone?

Started by Steve Wilson in sci.electronics.design1 year ago 35 replies

A google search shows a number of ways of running MS programs on android cellphones. One method suggests running Wine, then you can load...

A google search shows a number of ways of running MS programs on android cellphones. One method suggests running Wine, then you can load whatever EXE desired. Has anyone been able to run LTspice on android? How did you do it, and how well does it work? Thanks, -- The best designs occur in the theta state. - sw


simple opamp amplifier circuit

Started by panfilero in sci.electronics.design10 years ago 23 replies

I'm simulating on LTSpice, a simple amplifier circuit with a 2.5V offset, but if I don't include a capacitor on my input my output hits the...

I'm simulating on LTSpice, a simple amplifier circuit with a 2.5V offset, but if I don't include a capacitor on my input my output hits the rails... why is this? The link shows what I'm doing in LTSpice thanks http://i555.photobucket.com/albums/jj477/panfilero/Capture-1.jpg


A Brief Review of RF Oscillators in LTspice

Started by Steve Wilson in sci.electronics.design4 years ago 11 replies

Some people struggle to try to get an oscillator running in LTspice. This article describes different types of Colpitts and Clap oscillators snd...

Some people struggle to try to get an oscillator running in LTspice. This article describes different types of Colpitts and Clap oscillators snd shows how to calculate the component values to get them to run. Crystal oscillators are discussed, along with a method to drastically shorten the startup and settling time in order to view the actual oscillator waveforms. The descriptions are a...


hoe to draw bidirectional dc dc converter for dc nano grid in ltspice

Started by chetan in sci.electronics.design4 years ago 28 replies

I need to design nonisolated dc-dc bidirectional converter for dc nano gride system. i am not sure how to draw in ltspice or in Matlab. please...

I need to design nonisolated dc-dc bidirectional converter for dc nano gride system. i am not sure how to draw in ltspice or in Matlab. please help me out. --


ltspice nmos4 and pmos4

Started by Michael Robinson in sci.electronics.design11 years ago 3 replies

I have to simulate a CMOS circuit and I am going to try it in LTSpice. The dialog box where you can put in parameters for a mos4 device has no...

I have to simulate a CMOS circuit and I am going to try it in LTSpice. The dialog box where you can put in parameters for a mos4 device has no place to enter parasitics! That means I need a subcircuit. To save time is there anyplace where I can grab subcircuits for nmos4 and pmos4 devices? That would save a lot of time, I can just change the values.


LTSpice MESFET models

Started by Phil Hobbs in sci.electronics.design11 years ago 11 replies

Back on topic for a bit: I'm getting back to work on the biochip preamp, and I'd really like a more realistic SPICE model than the...

Back on topic for a bit: I'm getting back to work on the biochip preamp, and I'd really like a more realistic SPICE model than the behavioural ones I cobbled together previously. There are various models in the Avago literature for their ATF3x143 pHEMTs, but nothing that I can persuade LTSpice to swallow. They publish something called a Statz MESFETM1 model, as follows: Statz Mod...


LTspice model for DB3 DIAC

Started by P E Schoen in sci.electronics.design3 years ago 4 replies

I was trying to design a simple voltage relay in LTspice and I wanted to = use=20 a DIAC, but I had a hard time finding a model that worked....

I was trying to design a simple voltage relay in LTspice and I wanted to = use=20 a DIAC, but I had a hard time finding a model that worked. Finally I = found=20 the following in an obscure Japanese or Chinese website=20 http://bbs.dianyuan.com/topic/111118: * PSpice Model Editor - Version 9.2 *$ ********** *SRC=3DDB3; 32V 2A *DIAC *=B8=C4=B1=E4DZ=B5=C4BV=BF=C9=D2=D4=B8=C4=B1=E4Vbo ...


Small transformers and LTSpice simulation

Started by Grant in sci.electronics.design12 years ago 30 replies

I have a design that could use three or four winding toroid transformer. In the LTSpice notes they suggest keeping the transformer coupling...

I have a design that could use three or four winding toroid transformer. In the LTSpice notes they suggest keeping the transformer coupling at 1.0 or -1.0 otherwise there's lots of high frequency noise generated, I'm not sure if that's real world, or the simulation going silly? What I'm wondering is just how much coupling should I expect to see in a real world transformer of around f...


Numerical Optimizer (Solver) for LTSpice

Started by Anonymous in sci.electronics.design10 years ago 16 replies

I have written a numerical optimizer (solver) for LTSpice. It automaticall= y adjusts component values to meet circuit performance targets you...

I have written a numerical optimizer (solver) for LTSpice. It automaticall= y adjusts component values to meet circuit performance targets you set. Fo= r example maximum power output and minimum supply current. It uses a fast = evolutionary algorithm to get good results quickly. You can get good result= s in anything from 5 minutes to a few hours depending on the complexity of = the circui...


AN: TL598 Spice Model

Started by Jim Thompson in sci.electronics.design7 years ago 44 replies

Awhile back someone on the LTspice List requested a TL598 Spice model. While somewhat obsolete, it intrigued me, and proved to be somewhat...

Awhile back someone on the LTspice List requested a TL598 Spice model. While somewhat obsolete, it intrigued me, and proved to be somewhat of a !#$* to model... but it caused me to develop a few new functions in my behavioral modeling repertoire. It can be found at TL598.zip on the Device Models & Subcircuits Page of my website... including an LTspice symbol. Modeling is based only fro...


Colpitts crystal oscillator in LTSPICE

Started by bitrex in sci.electronics.design7 years ago 59 replies

I'm trying to simulate a low frequency Colpitts oscillator in LTSpice using an NPN darlington and a crystal, and I'm having a lot of trouble...

I'm trying to simulate a low frequency Colpitts oscillator in LTSpice using an NPN darlington and a crystal, and I'm having a lot of trouble getting it to start up. Does anyone have a working one of these? I'm just using a capacitor to simulate the crystal, the parameters I am working with are something like: motional capacitance: 5.3ff ESR = 11k ESI ~ 4500 henries EPR = 100 meg E...


LTspice tapped inductor

Started by Clive Arthur in sci.electronics.design3 months ago 18 replies

I have an inductor wound on some 22mm plastic pipe, so essentially air-cored. It's over 120 turns, 700mm long and uses resistance wire. It's...

I have an inductor wound on some 22mm plastic pipe, so essentially air-cored. It's over 120 turns, 700mm long and uses resistance wire. It's about 12uH. There are 30 capacitors connected evenly along the coil commoned to a copper pipe busbar. It simulates a long, peculiar transmission line. I want to LTspice it. OK, lots of small inductors with some resistance and the capacitors. ...


A current mirror variation on the Baxandall Class-D oscillator for producing a reasonable clean sine wave.

Started by Bill Sloman in sci.electronics.design2 years ago 8 replies

I've up-dated my website to add a circuit diagram, some comment on it, and the text from the corresponding LTSpice .asc...

I've up-dated my website to add a circuit diagram, some comment on it, and the text from the corresponding LTSpice .asc file. http://sophia-electronica.com/BillsBaxandall.html The circuit produces a balanced pair of 1V rms 17kHz sine waves. The LTSpice simulation suggests the third harmonic content is about 60db below the fundamental, and the fifth harmonic is even smaller. It's not a par...


"Mike Engelhardt has parted ways with Analog Devices"

Started by Simon S Aysdie in sci.electronics.design3 years ago 119 replies

"This does not bode well for the future of LTspice now that Mike Engelhardt has parted ways with Analog Devices."---analog spiceman...

"This does not bode well for the future of LTspice now that Mike Engelhardt has parted ways with Analog Devices."---analog spiceman https://groups.io/g/LTspice/topic/cloud_over_ltspice/71467233