Re: Looking for a IDT74CBTLV3253 model.

Modified version of "COUNTER TEST.asc" has been uploaded to Temp, named "COUNTER_TEST_works.asc".

I added the parameter needed to make the "counter" logic device actually count.

Andy

?

Re: Modelling an optoisolator

Hi, :

The following may be out of topic. But I am really curious about this...(and seeking for help, for those terminologies that I can't find out.)

I have searched the keywords like "led luminous intensity forward current math equation" in google.

But there are not such research results about those "If" through photo diode vs. lightening photons or intensity (whatever it's called) in math equation relations.

Could someone has any concept about this ?

The better is , if by the way the photo detector could be talked about.

Thank you

Best regards.

?

Re: Need help to design a transimpedance amplifier

#89990

That is quite easy. There lot of cmos type opamp with low drift spec. You can have t network on feedback which keep cost down for single opamp design. You also need cap on feedback to keep it stable.

Show quoted text

On 2 Aug 2016 20:24, "t.obulesu@... [LTspice]" <LTspice@...> wrote:
>
> ?
>
> Hello ?guys..
>
> I want to design a trans-impedance amplifier to detect currents of the APD (in the range of 200 nA to 100 micro A).
>
> Could some one suggest me the best IC with less bias current, single supply (+5 V only) and how to design a high sensitive TIA..? (typically, for every 100 nA change in the current, 100 mV voltage should be displayed).
>
>
>

Re: libraries for electronic components

#89989

gomezmemanuel?wrote:

? ?"I need to simulate the following MOSFET in LTSpice: 2sk3577, RJK0632JPD and 2sk1580."

I was going to recommend this: ?Sometimes you can't find a SPICE model for a transistor you want to use.? In that case, try to find an "equivalent" (or acceptable substitute) transistor for the ones you want.

There are ways to generate a SPICE model for a transistor from just the datasheet.? I have not done this myself.

Andy

Re: Looking for a IDT74CBTLV3253 model.

#90023

Gunoi Nare wrote:

? ?"As I said before, opening this file returns the error "Multiple flag.""

You are having a bad (corrupt) download.

Perhaps you are using Firefox, and perhaps you ask Firefox to open the file in LTspice.? Don't do that.

Instead, download and SAVE the file to your disk.? After it has downloaded and saved, then go to Windows Explorer, find the file, and then open it in LTspice.

Regards,

Andy

Re: Looking for a IDT74CBTLV3253 model.

Gunoi Nare

#89988

As I said before, opening this file returns the error "Multiple flag."

G.

Show quoted text

From: "basier.philippe@... [LTspice]"
To: LTspice@...
Sent: Monday, August 1, 2016 10:30 PM
Subject: [LTspice] Re: Looking for a IDT74CBTLV3253 model.

?

Hello Gunoi Nare

There are examples from Helmut with the A device counter in

Sorry, an error occurred while loading the content.

Preview by Yahoo

?

See A-counter_test;asc

Regards
PhB

Re: LTspice IV (NOT RESPONDING)

#89987

Jeff wrote:

? ?"I keep getting?LTspice IV (NOT RESPONDING),"

Can you tell us a bit more, please?

Does this happen when trying to install LTspice?? Or is it already installed, and this happens when trying to run LTspice?

Does it happen after clicking the desktop icon (or Start menu choice) to start LTspice?? Or does it happen after double-clicking on a schematic file to run LTspice and open the schematic?

Or does it happen when doing a simulation (after clicking the running-man icon)?

Or does it happen when LTspice is drawing a waveform plot?

Does it always happen, or only some of the time?

Andy

Re: Need help to design a transimpedance amplifier

#89986

Hello,?t.obulesu:

For log amp, there is a (TI) log112 model at the file folder, you could take reference of the following:

?

It shows some .TRAN issues, if you could fix it, maybe you could feedback to the file folder.

If you need really to implement one instance, there is a technique could average the background noise "white noise".

It utilizes the op amp in voltage-follower (multiples in parallel) to averaging the noise (normally it's called "white noise"), it's not eliminated but averaged.

It might be helpful. If you finally get helped from those techniques, feedback the forum, show how it take effect, lightly or significant.

if so, everyone should appreciate you.

Good day!

Best regards.

Re: Unable to find InstName attribute in LTSpice for mac

#89984

Hello,

I rarely use a MAC.?

I have tried now to add <InstName> to a new symbol, but I also couldn't find a menu to do this.

I have sent an email to Mike, the author of LTspice. Let's see what he will answer.

".... how to add the? <InstName> to a symbol in the symbol editor of MAC-LTspice."

Best regards,

Helmut

Re: LTspice IV (NOT RESPONDING)

#90015

...some of the anti virus-ware programs can slow down win7 and windows10.

To check this you would need to uninstall your virus-ware and go offline and check LTSPICE.

Or if you don't have enough RAM ( I have 12 GB on a multi-core i7 Dell system..and still get slowdowns

on some software)....see if you have something like 4GB RAM installed and your system only sees 2 GB.

If none of this helps...and/or uninstalling your virus-ware doesn't change anything email the Microsoft

Gurus..or visit their chat boxes at:?

W. Warren

?

Re: Mechanical switch

#89983

Hello David,

You could make a bouncing switch with a V-source (PWL) as the control voltage for a switch SW.

You can see a "typical" bouncing switch on the top-left picture.

?

Best regards,

Helmut

Re: Need help to design a transimpedance amplifier

#89982

开云体育

You have an impossible set of criteria for a linear TIA. You ask for 100mV per 100nA. 100uA is 1000 times larger than 100na. So, your spec would have 1000 times 100mV out with 100uA in, or 100V. You obviously cannot get that with a 5V only system! Your choices are to reduce sensitivity or use a logarithmic TIA circuit.

Jim

James Wagner

Oregon Research Electronics

Show quoted text

On Aug 1, 2016, at 8:47 PM, t.obulesu@... [LTspice] <LTspice@...> wrote:

Hello ?guys..?

I want to design a trans-impedance amplifier to detect currents of the APD (in the range of 200 nA to 100 micro A).?

Could some one suggest me the best IC with less bias current, single supply (+5 V only) and how to design a high sensitive TIA..? (typically, for every 100 nA change in the current, 100 mV voltage should be displayed).

Re: Input impedance of an energy saving fluorescent lamp (CFL) 21W

#89981

CFL Circuit
13 Watt 120 VAC Compact Fluorescent 

Bordodynov.

02.08.2016, 19:04, "Jerry Lee Marcel jerryleemarcel@... [LTspice]" <ltspice@...>:

Show quoted text

CFL's are very non-linear, in fact exhibit negative resistance. There are a few Spice models on the internet, you may have to adapt them for LTspice.

Le 02/08/2016 à 17:42, michael883575@... [LTspice] a écrit?:

I am attempting to simulate a loaded inverter using the equivalent input impedance of the CF lamp as the load. Is there anybody in the group who might have an idea as to what a typical value for example for a 21W lamp might be.

Thank you very much in advance

Michael----------------------------------------

L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
www.avast.com

Re: Input impedance of an energy saving fluorescent lamp (CFL) 21W

#89978

开云体育

CFL's are very non-linear, in fact exhibit negative resistance. There are a few Spice models on the internet, you may have to adapt them for LTspice.

Le 02/08/2016 à 17:42, michael883575@... [LTspice] a écrit?:

?

I am attempting to simulate a loaded inverter using the equivalent input impedance of the CF lamp as the load. Is there anybody in the group who might have an idea as to what a typical value for example for a 21W lamp might be.

Thank you very much in advance

Michael?

L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.

Re: LTspice IV (NOT RESPONDING)

John Woodgate

#89985

开云体育

It's because your computer is being slowed down. Maybe you need to run a tune-up application. Just emptying some files, like Temp and Recycle Bin might help. Defrag the hard drive, too, if you can leave the computer on for a long time while not in use.

?

With best wishes DESIGN IT IN! OOO – Own Opinions Only

J M Woodgate and Associates Rayleigh England

?

Sylvae in aeternum manent.

?

Show quoted text

From: LTspice@... [mailto:LTspice@...]
Sent: Tuesday, August 2, 2016 4:33 PM
To: LTspice@...
Subject: [LTspice] LTspice IV (NOT RESPONDING)

?

I keep getting?LTspice IV (NOT RESPONDING), My thinking is that LTspice is busy loading the info it wants or my computer is busy, but it only happens with LTspice,?

Computer is Toshiba Laptop running Window 7 (I don't like 10) any ideas or do I just need to be more patient? It does finally respond and do what I asked for.

?Thanks,

Jeff

?

Mechanical switch

#89979

Where could I find a model of a real mechanical switch, including sparking during opening?

I'm interested in spark gaps in general, but particularly a switch (voltage controlled ideally) that behaves like a real switch WRT arcing when used with inductive loads.

I am only partially "on" the list here, my access does not include file downloads or web access to the group.

--

K1FZY (WA4TPW) SK? 9/29/37-4/13/15

Input impedance of an energy saving fluorescent lamp (CFL) 21W

#89977

I am attempting to simulate a loaded inverter using the equivalent input impedance of the CF lamp as the load. Is there anybody in the group who might have an idea as to what a typical value for example for a 21W lamp might be.

Thank you very much in advance

Michael?

LTspice IV (NOT RESPONDING)

#89976

I keep getting?LTspice IV (NOT RESPONDING), My thinking is that LTspice is busy loading the info it wants or my computer is busy, but it only happens with LTspice,?

Computer is Toshiba Laptop running Window 7 (I don't like 10) any ideas or do I just need to be more patient? It does finally respond and do what I asked for.

?Thanks,

Jeff

Unable to find InstName attribute in LTSpice for mac

#89975

I'm trying to create a symbol in LTSpice for mac.
I've to place the InstName attribute but I'm doing right click -> view -> Attribute table and it's not there

Re: libraries for electronic components

#89974

.ummm, the best suggestions starting out is to Google the data sheets and see if those devices

match up any of the circuits that have already been modeled around here.

Have you designed and run a MOSFET simulation with LTSPICE yet?

Might be a good place to start.

Here are some useful URLs:

?? <---MOSFET docs

? <---LTSPICE tutorial

?? <---MOSFET modeling

? <---paper

?? <---youtube instructional video

W. Warren