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Okkar Moe Myint <okkarmoemyint@...> wrote:

..

. I could not find the library for MAX4173H which is a high side current
sense.
...

This webpage:



has a "macromodel" (which is a SPICE model) for the MAX4173T. The
difference between the 'T' and the 'H' version seems to be the part's
voltage gain. If you can only use the 'H' version, it might be possible to
modify the 'T' version's macromodel.

Macromodels are models of simplified versions of the actual circuitry.
Sometimes a block, such as an op-amp, is represented by a VCVS, which
simulates faster than a couple dozen transistors that actually comprise the
op-amp.

This macromodel is a SPICE "subcircuit", so you would use it as a
subcircuit. There must be hundreds of messages already in this group about
how to use a subcircuit model in an LTspice simulation.

This webpage:



has an Orcad (PSPICE) library for the same part. The model looks very
similar. LTspice is very compatible with PSPICE, so that one probably
works just fine too.

Regards,
Andy

--- In LTspice@..., "analogspiceman" <analogspiceman@...> wrote:

--- In LTspice@..., Helmut <helmutsennewald@> wrote:

--- In LTspice@..., analogspiceman wrote:

--- In LTspice@..., Helmut <helmutsennewald@> wrote:

I always wonder that 1999 was the "birth" of LTspice.
I personally discovered that LTspice is a SPICE program in
the summer 2001. I still believe that I was one of the early
adopters using it as a general SPICE program. Also the
discussions about LTspice started in 2001 in the usenet,
sci.electronics.design and sci.electronics.cad.

A trademark information search on "LTspice" yields:

First Use Anywhere: . .10/1/1999
First Use In Commerce: 10/1/1999

The Help about box shows a copyright back to 1998.

The earliest messages about SwitcherCAD III, SwitcherCAD3 or
LTspice that I could find were in June of 2001. Some trade
magazine articles about LTspice also came out in June 2001,
so LTspice must have been available in at least May 2001.
Perhaps it was quietly available in 2000. I might send Mike
a link to the LTwiki page and ask for his input (or perhaps
the question might be received more favorably coming from you).

Hello analogspiceman,

I have sent an email to Mike and asked him about comments and
corrections.

Thanks, Helmut. I went ahead and also sent him an email, but
your support is appreciated. ... What? He just now replied,
wrote that he's off to Australia, but answered with some
interesting tidbits (and will give a more complete answer when
he gets back.

"LTspice was released in Oct 1999 at a meeting of Linear
Technology's Field Application Engineers. They were then free
to give it to customers they met on a visit-by-visit basis."

Hello analogspiceman,

Now I know why I have seen LTspice only later in 2001. Maybe
our FAE overlooked my interest in LTspice. :-)

Best regards,
Helmut

--- In LTspice@..., Helmut <helmutsennewald@...> wrote:

--- In LTspice@..., analogspiceman wrote:

--- In LTspice@..., Helmut <helmutsennewald@> wrote:

I always wonder that 1999 was the "birth" of LTspice.
I personally discovered that LTspice is a SPICE program in
the summer 2001. I still believe that I was one of the early
adopters using it as a general SPICE program. Also the
discussions about LTspice started in 2001 in the usenet,
sci.electronics.design and sci.electronics.cad.

A trademark information search on "LTspice" yields:

First Use Anywhere: . .10/1/1999
First Use In Commerce: 10/1/1999

The Help about box shows a copyright back to 1998.

The earliest messages about SwitcherCAD III, SwitcherCAD3 or
LTspice that I could find were in June of 2001. Some trade
magazine articles about LTspice also came out in June 2001,
so LTspice must have been available in at least May 2001.
Perhaps it was quietly available in 2000. I might send Mike
a link to the LTwiki page and ask for his input (or perhaps
the question might be received more favorably coming from you).

Hello analogspiceman,

I have sent an email to Mike and asked him about comments and
corrections.

Thanks, Helmut. I went ahead and also sent him an email, but
your support is appreciated. ... What? He just now replied,
wrote that he's off to Australia, but answered with some
interesting tidbits (and will give a more complete answer when
he gets back.

"LTspice was released in Oct 1999 at a meeting of Linear
Technology's Field Application Engineers. They were then free
to give it to customers they met on a visit-by-visit basis."

He <he.yang@...> wrote:

Is there a susceptance in LTspice, that i can direct use?


A capacitor, or an inductor, are susceptance elements.

You might want to make sure they have no parasitic resistances, so that
your component has only susceptance and no conductance. Unless you also
want it to have conductance.

Andy

--- In LTspice@..., "shravan.krishna7@..." <shravan.krishna7@...> wrote:

I am a beginner of LTspice. Please would someone tell the procedure of adding INA105 pspice model into LTspice?

Hello,

I have looked for similar part and found an example with the
INA132. It was easy to modify this part for teh INA105.

Files > Lib > INA105_test.zip


Open the symbol with the symbol editor of LTspice and study
the attributes and the "Netlist order" in the pins. This
netlist order is simply the order of the pins in .subckt.
It's not the name or number of these subcircuit-pins.

Best regards,
Helmut

Hello,

I've checked this with a Bsource both two syntaxes work fine

b3 n001 0 v=(pow(-1,round((- 2 *((1)-1)/2+1)/- 1)))

b1 n002 0 v=(-1)**round((- 2 *(1 -1)/2+1)/- 1)

With a bsource using a function directive only one works

b3 n001 V=ch2(zz) neither V=ch3(zz) wrong

b3 n001 V=ch4(zz) good

.param a=2 b=1 zz=1

.func ch2(x)=(-1)**round((-a*(x-1)/2+1)/(-1)/b); ==> errorlog
(-1)**round((- 2 *(( 1 )-1)/2+1)/(-1)/ 1 ?))?

.func ch3(x)=(-1)**round((-a*(x-1)/2+1)/-b) ; ==> errorlog
(-1)**round((- 2 *(( 1 )-1)/2+1)/- 1 ?))?

.func ch4(x)=pow(-1,round((-a*(x-1)/2+1)/-b)) ; ==> good



I'am sure that two syntaxes were correct before because almost all
the files in the below section provide errors

Files > Examples > Educational > Power_Conditioning



Regards

Didier

--- In LTspice@..., "analogspiceman" <analogspiceman@...> wrote:

--- In LTspice@..., "Helmut" <helmutsennewald@> wrote:

I always wonder that 1999 was the "birth" of LTspice.
I personally discovered that LTspice is a SPICE program in
the summer 2001. I still believe that I was one of the early
adopters using it as a general SPICE program. Also the
discussions about LTspice started in 2001 in the usenet,
sci.electronics.design and sci.electronics.cad.

A trademark information search on "LTspice" yields:

First Use Anywhere: 10/1/1999
First Use In Commerce: 10/1/1999

The Help about box shows a copyright back to 1998.

The earliest messages about SwitcherCAD III, SwitcherCAD3 or LTspice
that I could find were in June of 2001. Some trade magazine articles
about LTspice also came out in June 2001, so LTspice must have been
available in at least May 2001. Perhaps it was quietly available in
2000. I might send Mike a link to the LTwiki page and ask for his
input (or perhaps the question might be received more favorably
coming from you). :)

Hello analogspiceman,

I have sent an email to Mike and asked him about comments and corrections.

Best regards,
Helmut

Good point viable info is obtained through research don't wear out one resource!!! No rudeness implied but come on.....

Joseph

Hi All,

I like to ask you guys a favor. I could not find the library for MAX4173H which is a high side current sense. Can anyone help me how I can create a new part? I am totally new to LTspice. Thanks

Okkar

--- In LTspice@..., Jim Wagner <wagnejam99@...> wrote:

So, maybe one of the important anchor points in your timeline
ought to be when GUIs began to be made as an integral part of
the various spice versions.

From high school I remember paper tape and I briefly used punch
cards at university in engineering course work. Output was ascii
graphics on line printers as you mentioned (some students would
generate heavy patterns of text in order to generate specific
frequencies of sound in an attempt to play songs - the waste of
ink and paper irritated the operators).

Terminal graphics were supposedly introduced with SPICE 3, but
ordinary students didn't have access to CRT terminals. I think
PSpice (which used to be called uPspice, if memory serves) was
the first popular SPICE for the IMB PC and, thus, represents
the beginnings of the GUI's mainstream influence (which is one
the reasons I included it on the road to LTspice). -- a.s.

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:

I always wonder that 1999 was the "birth" of LTspice.
I personally discovered that LTspice is a SPICE program in
the summer 2001. I still believe that I was one of the early
adopters using it as a general SPICE program. Also the
discussions about LTspice started in 2001 in the usenet,
sci.electronics.design and sci.electronics.cad.

A trademark information search on "LTspice" yields:

First Use Anywhere: 10/1/1999
First Use In Commerce: 10/1/1999

The Help about box shows a copyright back to 1998.

The earliest messages about SwitcherCAD III, SwitcherCAD3 or LTspice
that I could find were in June of 2001. Some trade magazine articles
about LTspice also came out in June 2001, so LTspice must have been
available in at least May 2001. Perhaps it was quietly available in
2000. I might send Mike a link to the LTwiki page and ask for his
input (or perhaps the question might be received more favorably
coming from you). :)

I am a beginner of LTspice. Please would someone tell the procedure of adding INA105 pspice model into LTspice?

--- In LTspice@..., "oleka111" <oleka111@...> wrote:

Nice to see that you spotted it too......
What if real circuit would behave the same way ?
Hope Linear will fix this issue soon.
I didn't post the original file, because everyone can load it as an LT's example named 3765.asc and see the effect of diminishing of the voltage feedback resistor.

Regards,
Olek A.

--- In LTspice@..., "Tony Casey" <tony@> wrote:

--- In LTspice@..., "oleka111" <oleka111@> wrote:

Hello,

Running an dc/dc example named 3765.asc with slightly lowered feedback resistor (4.42 --> 4.2k) gives Vout appr. several times bigger than expected.
Just the opposite what we should expect while lowering the feedback resistor.
It can be even dangerous to the sensitive load.

Why it behaves this way ?

Hello,

Well spotted. I have tried this distribution example circuit on two machines, and it behaves as you describe.

I swept the feedback resistor from 4k1 to 4k3 in 10R steps and found that the LTC3766 transitions from closed loop to open loop behaviour when the value goes below 4210R. Whether this a model error or not, I don't know, but the example circuit is clearly unsatisfactory.

I have reported this as a bug to Mike.

Regards,
Tony

I have received a response from Linear (not Mike - I think he must be on holiday).

Basically, what they say is that the behaviour is as expected, and related to the undervoltage lockout on Vcc, which is connected to the regulated output in this circuit, and that this is operating the device somehow incorrectly because of that.

However, the LTspice simulation is almost exactly the same as the application circuit in the datasheet (with the exception that the output is not floating), and the simulation would suggest it won't work as published with 5% resistors.

The datasheet says: the minimum Vcc voltage is 5V, and that the regulated DC voltage must be above this if it supplies Vcc directly, or an overvoltage condition can occur. So, this is kind of a known "feature". With zero tolerance resistors, the calculated regulated output voltage is (1 + 4.42k/604)*599.6mV, which is 4.987V, so this is never going to work in the real world.

This is what the LT response actually said:
"Alright the jig circuit shows that you can use 4.42KOhm, and it is not suppose to take that as the real design. If you want the design close to the scenario, you need to go through from more realistic perspective.

Anyway, the model is right, and the jig is right. If you argue that the circuit is not a robust design, that is not the issue of the model. Many times our jig circuits show simplified setup, for example, more ideal magnetic devices, no ESL of sensing resistor, down sized soft-start cap, etc. It is there for user to quickly pick up the fundamental features of the part, and we encourage users to design their applications based on that."

For what it's worth, I modified the schematic so that the Vcc pin was fed from a separate 5V supply and reduced the feedback resistor to 4k1 (from 4k42), and the output did regulate properly at 4.67V.

Hope that helps somebody.

Regards,
Tony

Hallo,
Is there a susceptance in LTspice, that i can direct use? thank u!
Regards
He Yang

With 100Ohm load I got these results (rval is the value of R11 in the
scheme):
from error log with .MEAS TRAN res1 FIND V(out) AT=0.88m
.step rval=4300
.step rval=4200
.step rval=3900


Measurement: res1
step v(out) at
1 4.99022 0.00088
2 4.88817 0.00088
3 4.7575 0.00088
4 6.25114 0.00088
It is the same behavior as with 1KOhm load but the critical value of R11
is lower.
Regards.
Varoli

--
Prof. Vincenzo Varoli
Politecnico di Milano Dip. Energia
Via G. Ponzio 34/3 I20133 Milano Italia
Tel. 0223996393 FAX 0223996309

Hello Olek,
Have you tried with more load, e.g. 100Ohm instead of 1kOhm?
Best regards,
Helmut

Nice to see that you spotted it too......
What if real circuit would behave the same way ?
Hope Linear will fix this issue soon.
I didn't post the original file, because everyone can load it as an LT's example named 3765.asc and see the effect of diminishing of the voltage feedback resistor.

Regards,
Olek A.

That one is easy. Its "just" a couple of op-amps. follow the block diagram in the spec sheet and you pretty much have it.

Jim Wagner
Oregon Research Electronics.

Hello, a.s.

I'm impressed by the work you have put in on this.

I would like to add one note, which I have peripherally mentioned in the list before. Newcomers are likely to not remember or never have known what the "state of computing" was when spice began in the early 1970s. I encountered it on machines limited to punch-card input and line printer output, only. You submitted "job decks" (and some still refer to a netlist as a "spice deck"); woe unto you who dropped one of those punch card boxes! And the reams of fanfold paper needed to print out the initial node conditions plus the response of selected nodes. The response was an "ASCII graph" with an even time step. I don't know if it was computed on an even time step or if it was interpolated after the fact.

An important part of this as that as long as the machine ran FORTRAN, accepted punch card input and did line printer output, spice would run. There were no issues of "operating system" or cross-platform behavior. I saw it run on big IBM mainframes and CDC6400s.

I think that it was the graphic user interface that really pushed various implementations into one OS or another. It was simply too hard to do a two-OS implementation (for the most part).

So, maybe one of the important anchor points in your timeline ought to be when GUIs began to be made as an integral part of the various spice versions.

Thans for all your great work.

Jim Wagner
Oregon Research Electronics

--- In LTspice@..., "sawreyrw" <sawreyrw@...> wrote:

I understand that, but there is no function of frequency shown at that link. If you don't think that is the case, double check it.

Rick

My mistake. Here's the web page and correct link:





Other related stuff there.

RL