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Sub ckt

 

I need a simple 1 transistor circuit example with the transistor using a subckt and the attached file and location of file called out. I want to standardize my oth files to it. Please give example. Fwd to Zardos49@...
Sent from my BlackBerry? by Boost Mobile
Mitsubishi-Renesas M51978FP controller SPICE model

[email protected]
 

Hello, I am trying to find this Spice model or similar? to understand how a 220V SMPS I have works.
I want to modify it to source 12V 3A instead of 7-10 V 3A as for now.
I have drawn the secondary side on ltspice but I cannot make it simulate it nor phisically work? correctly, it keeps going into limit mode.
It uses 2 opamps lm358 and 2 comparators lm393 and a PC113 optoisolator feedback and the M51978FP.
For the simulation part, since I haven't a Spice Model for the M51978FP, I tried to use a Voltage controlled switch tied to the opto and a Voltage source with a triangular wave but I cannot get the system to start.
I tried to inject a Pulse Voltage on the control side to kick start but even then it does not allow the triangular wave to build up a voltage.
If someone is interested to discuss this issue I can publish the circuit and info I got so far.
Thanks

I uploaded the data sheet on the temp directory.
Re: A three Phase question please

 

Thanks interesting

I know that you can use a considerably smaller core at 500 Hz and less windings per volt. This is where the weight savings occur for avionics use.

I I have thought about the use of a switched mode, mainly for valve amplifiers, but wonder about the extremes of generating 800V DC at high frequency. I have not seen high speed rectifiers with greater than a 100 V rating. I guess that they exist, but the price tag is prolly horrendous and or the supply limited to defence contractors only.

The circuit I'm playing with, dates from WW2. It discharges 0.7 Joules in 2uS every 20mS (350Kw) into a 24:1 step up transformer¡­ Yes 10kV pulses¡­ Everything about this circuit is extreme.

Best regards


Suusi M-B
Re: CIC unstable output

 

Vlad,

I was out of town for a couple of days, and have yet to catch up on all my emails.

But I was wondering, do we know that the system being simulated is stable? ?Can you, and have you, made a digital model of the CIC interpolator and does it behave properly? ?Are there ways to measure the stability, to tell that it is not on the edge of instability, for example?

Andy
Re: CIC unstable output

 

At least does anyone know why the samples lose their constant-time values? Because adding?(one or more)?S&H between stages makes the output correctly sampled but awfully wrong. Is it because of the large number of integrator stages? It doesn't happen that way if you change it into a CIC decimator (and there are really large values after the upsampler).



Vlad
Re: Spice model

 

Thank you andy and john.
Re: Yahoo Search Broken?

monettsys
 

--- In LTspice@..., John Woodgate <jmw@...> wrote:

In message <l91pdi+glof@...>, dated Fri, 20 Dec 2013, d4394548
<nodoh@...> writes:

OK, Here I am as user D4394548 with a completely different identity and
emal address. Still goes to
as it did before. So I'm SOL on search:)
I think that pins it down to the server your messages go to: it's not
re-directing to the neo page.
Yes. It used to go to neo depending on how I logged in. But now it doesn't matter - it always goes to no matter what I do.

You are not shown as a member with that username yet.
Maybe it took time to update the log. Anyway, Yahoo accepted the post under that username, but still went to the same page and search was still broken.

I deleted the new membership to keep the logs in order. Now I have to figure out how to get a copy of the 72k posts so I can search offline.

It shouldn't be too big. Yahoo has a 100MB limit. I could put it on my website and get it indexed by google so others with the same problem could do searches. How would I go about getting permission from the members to do that?

Thanks,

Mike
Re: Yahoo Search Broken?

 

On 20/12/2013 22:01, Peter Johansson wrote:
On Fri, Dec 20, 2013 at 3:46 AM, monettsys <405a82e5@...> wrote:

Is anyone else having problems searching the forum?
No it works well for me. The box says "search conversations" and I put something in and hit enter and the results pop up. Occasionally it pops up with a group search but going back to the group home page seems to sort it out. Pressing enter rather than having a button to press is a bit un-intuitive. I checked in IE 10, Chrome and Firefox. I would expect older versions of IE to have problems but they will probably have issues with other sites as well...
Yahoo's forum search isn't the greatest even when it does work.
Archive all your list traffic in gmail and let google search it.
Obviously this will not search any of the traffic before you
subscribed, but the sooner you start doing this the sooner it will be
useful.

-p.
Re: Yahoo Search Broken?

 

Re install
Sent from my BlackBerry? by Boost Mobile
From: "monettsys" <405a82e5@...>
Sender: LTspice@...
Date: Fri, 20 Dec 2013 23:00:15 -0000
To: <LTspice@...>
ReplyTo: LTspice@...
Subject: [LTspice] Re: Yahoo Search Broken?

?

--- In LTspice@..., cbayona <CBayona@...> wrote:
>
> I went back and the search option is gone, that is why I use a mail
> client and keep the emails that are important, the web site is a disaster.

I just tried to reply to your post, but Yahoo skipped the original quote text and just gave a blank screen.

After clearing the Firefox cache and logging on several times, your original text suddenly appeared.

Search is still broken.

I also keep the good posts, but that only goes back a couple of years. Lost the rest in a disk crash. I have a much better backup system now.

So how do we find information in posts that may go all the way back t the beginning? I think Helmut keeps a copy of everything. Maybe we could ask him to put a copy on DVD and mail it to us. A small sum to defray the cost and time would be appropriate.

The other problem is the format. I believe something like this was done either in this forum or another one. But the program that downloaded the files from Youtube saved them in a funny format that required a special reader. So if you wanted to use grep or some other search program, you were SOL.

Isure would be happy to move to some other method and dump Yahoo. It has been such a pain for many years.

Most of the other methods can send copies to various mail archinve services. These are indexed by google so you can search using all the google search options. Much faster and easier than Yahoo ever was.

Thanks for your info,

Mike

Thanks,

Mike
Re: Yahoo Search Broken?

monettsys
 

--- In LTspice@..., cbayona <CBayona@...> wrote:

I went back and the search option is gone, that is why I use a mail
client and keep the emails that are important, the web site is a disaster.
I just tried to reply to your post, but Yahoo skipped the original quote text and just gave a blank screen.

After clearing the Firefox cache and logging on several times, your original text suddenly appeared.

Search is still broken.

I also keep the good posts, but that only goes back a couple of years. Lost the rest in a disk crash. I have a much better backup system now.

So how do we find information in posts that may go all the way back t the beginning? I think Helmut keeps a copy of everything. Maybe we could ask him to put a copy on DVD and mail it to us. A small sum to defray the cost and time would be appropriate.

The other problem is the format. I believe something like this was done either in this forum or another one. But the program that downloaded the files from Youtube saved them in a funny format that required a special reader. So if you wanted to use grep or some other search program, you were SOL.

Isure would be happy to move to some other method and dump Yahoo. It has been such a pain for many years.

Most of the other methods can send copies to various mail archinve services. These are indexed by google so you can search using all the google search options. Much faster and easier than Yahoo ever was.

Thanks for your info,

Mike

Thanks,

Mike
Re: Switch ... on - Switch... off

 

Ok Andy, now it's clear, many thanks.
Enrico
Re: Yahoo Search Broken?

 

On Fri, Dec 20, 2013 at 3:46 AM, monettsys <405a82e5@...> wrote:

Is anyone else having problems searching the forum?
Yahoo's forum search isn't the greatest even when it does work.
Archive all your list traffic in gmail and let google search it.
Obviously this will not search any of the traffic before you
subscribed, but the sooner you start doing this the sooner it will be
useful.

-p.
Re: LMV431

 

Hello Mario,

May be the model of the TLV431 is a good fit.

All Files > Lib > TLV431

http://groups.yahoo.com/neo/groups/LTspice/files/%20Lib/TLV431%20/

Best regards,

Helmut
Re: Switch ... on - Switch... off

 

Enrico wrote:

? "I thank you Andy, but i've made a small circuit with one switch ON and another OFF and they work exactly the same, so i don't understand the difference."

Both S1 and S2 switches are controlled from the same voltage, 'b'. ?So they must work exactly the same.

I believe the optional "on" and "off" parameters, with the Switch device, are aides or hints to LTspice, about its initial conditions. ?Occasionally, SPICE has difficulty figuring out whether a device such as a diode or a transistor should initially be ON or OFF when it does the initial transient solution. ?Adding that parameter is used as an initial guess, to help LTspice decide whether the switch (or diode or transistor) should initially be ON. ?Other than making it easier to solve for the initial conditions, it does not affect the rest of the simulation. ?Ultimately (except for that initial guess), the state of the switch is determined only by its control voltage.

Regards,
Andy
Re: Spice model

 

partho.duet?wrote:

? "But I knew that in Ltspice models are .spi, .cir and .net formet. I have face problem that there dodes not create symbol automatically in .mod format."

The filename (filetype or extension) makes no difference.

What matters is what is inside the file.

For a transistor, the contents of the file should USUALLY begin with:

.MODEL ....

Occasionally a transistor model may be more complicated and contain a .SUBCKT section.

So, open the file and examine its contents.

Andy
Re: Yahoo Search Broken?

 

Many of YahooGroups' functions seem to work for most people but not for others. ?I read regularly about this happening. ?Problems come and go ... and come and go again and again. ?Yahoo hasn't yet learned the old saying, "if it ain't broke, don't fix it."

I think the situation is that the bugs are all over the place, and Yahoo's servers do not all behave the same on any given date. ?You may just need to wait it out until it works again for you.

Andy
Re: Yahoo Search Broken?

cbayona
 

I went back and the search option is gone, that is why I use a mail client and keep the emails that are important, the web site is a disaster.

At 09:29 AM 12/20/2013, you wrote:
--- In LTspice@..., cbayona <CBayona@...> wrote:

No problem here including searching, I use the link at the bottom of
each email.
?? You must have a completely different system from me. I was referring to the search window at the top right of the message page in the forum.

If you click on a post to read it, the search box moves the the top center of the page.

Neither search works in , but apparently it works fine in neo.

Thanks,

Mike
--
Cecil - k5nwa
< > < >

Never take life seriously. Nobody gets out alive anyway.
Re: Yahoo Search Broken?

 

¿ªÔÆÌåÓý

Hi Mike

I just tried and got to


Seems to be ok, search too.

Al D.
On 12/20/2013 03:46 AM, monettsys wrote:
Is anyone else having problems searching the forum?
When I log on, no matter what I do, I am always taken to

Note there is no NEO in the url. I used to be able to go there, but not anymore.
However, when I try to do a search, for example, "tl494", I always get the following message:

-- 

AC2CL 

I do not think there is any thrill that 
can go through the human heart like that felt by the inventor as 
he sees some creation of the brain unfolding to success... 
Such emotions make a man forget food, sleep, friends, love, everything. 

- Nikola Tesla

Re: A three Phase question please

 

¿ªÔÆÌåÓý

Hi Guys

Actually, you can use a 50/60 Hz xfmr up there at 500Hz just fine
with no extra core dissipation.
The flux density is reduced due to the mag current being proportionately less.
the losses are roughly the same.

Its just that they dont do that for aircraft supplies due to weight.

These days with SMPS, who uses big iron any more?

Al D.
On 12/19/2013 06:46 PM, John Woodgate wrote:
smalcolmbrown@... writes:

>The three phase is 36Vac 500Hz which really chucks a spanner in the
>transformer design.

The main issue is to get the thin laminations you need for 500 Hz. I
suppose they are available, as used in aircraft transformers, but maybe
really difficult to get in small quantities.

-- 

AC2CL 

I do not think there is any thrill that 
can go through the human heart like that felt by the inventor as 
he sees some creation of the brain unfolding to success... 
Such emotions make a man forget food, sleep, friends, love, everything. 

- Nikola Tesla

Re: Yahoo Search Broken?

John Woodgate
 

In message <l91pdi+glof@...>, dated Fri, 20 Dec 2013, d4394548 <nodoh@...> writes:

OK, Here I am as user D4394548 with a completely different identity and emal address. Still goes to as it did before. So I'm SOL on search:)
I think that pins it down to the server your messages go to: it's not re-directing to the neo page.

Now I have to unscramble Firefox passwords and delete the membership to the forum so I don't screw up Helmut's member logs.
You are not shown as a member with that username yet.
--
OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk
Nondum ex silvis sumus
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
89461 - 89480 of 157804