Re: Looking for a IDT74CBTLV3253 model.

PhB wrote:

? ?"I did try to open??directly from my web browser (Firefox) [by open the link in a new ] and I got the error message :

multiple instances of "Circle""

Yup.? That is exactly what we expected. ?(Thanks for confirming it.)

Gunoi Nare has to make sure he/she does not open it that way.? Then the problem stops.

Andy

Re: No XP?

#90228

? ?"Why do you think t that? LTspice XVII libraries could not be used with LTspice IV ?"

That's what I wondered too.

Because the "new library" that comes with LTspiceXVII is (essentially if not exactly) the same as the "old library" that comes with LTspiceIV.

However, I think Gunoi Nare is suggesting having Analog Device's models become more compatible with LTspiceIV.

This should be a question for Mike Engelhardt, who actually works for LTC and controls LTspice.? Everyone should know how to contact him (see Help -> About LTspiceIV).

But it should be mentioned that many of ADI's SPICE models already are compatible with LTspiceIV.? The problem, is that some of them are poorly made or do not work right.? So I suppose the request really was to "fix" ADI's models to make them actually work better or work right.? That would be a tall order (a lot of work for anyone to do).

ADI's former Hittite products are in the RF domain where most engineers choose to use other tools and not SPICE.? So there might not be any SPICE models for them.? I don't know why Gunoi Nare singled out Hittite.? ADI has other companies whom they acquired over the years too. ?(Remember PMI?)

Andy

Re: Looking for a IDT74CBTLV3253 model.

#90227

Hello Andy

I did try to open directly from my web browser (Firefox) [by open the link in a new ] and I got the error message :
multiple instances of "Circle"

Regards
PhB

Re: ....list

#90226

W. Warren wrote:

? ?"Helmut Sennewald and Michael Englehardt..PLEASE notify us if and when you are publishing or selling any

? ? books of yours.?? NO there was not even a "user manual" listed under your names..."

I am not either of them ...

But I am pretty much certain that neither Helmut nor Mike has written a book about LTspice.? So it is not surprising that nothing comes up written by them.

Well, Mike did write the Help utility that comes with LTspice, and it has been formatted into a PDF file from time to time, so I guess you could call that a "book".? But he has never "published" it for sale, and he doesn't take personal credit as its author.? It is just the Help that comes with the program he created.

Andy

Re: @ Helmut. Re: Looking for a IDT74CBTLV3253 model.

#90225

? ?"No mater what I do, when the file is opened the error "Multiple circles" is displayed."

?Did you save them to your computer first, and THEN open them from the disk?

Do not open them from your web browser.? Instead, save them to a file on your computer's hard drive.? Then shut down your web browser (not necessary, but it makes sure the file was fully saved and closed).? Then double-click on the filename to open it in LTspice.

Whether or not this was the cause of the errors, the problem exists with your computer, not with the files that you tried to download. ?(Your computer is corrupting those files, probably because you did not download them properly.)

Andy

....list

#90224

...for now anyway.

List of everything (searchable and in English...check for German, French, Chinese and Russian versions)

...for "LTSPICE" (not Spice or "electronic simulators"):

?

Helmut Sennewald and Michael Englehardt..PLEASE notify us if and when you are publishing or selling any

books of yours.?? NO there was not even a "user manual" listed under your names...IF you do have books

available (or to be released) contact your publisher and ask them "why am I not searchable on the Internet"?

W. Warren

Re: Looking for a IDT74CBTLV3253 model.

#90223

Hello Gunoi Nare

Have you read my and Andy's last message (August 3) ?

"..., and perhaps you asked your web browser 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 "

Don't try to open an asc file directly from your browser !!!!!!!

Regards

PhB

Re: @ Helmut. Re: Looking for a IDT74CBTLV3253 model.

Gunoi Nare

#90222

Helmut.

No mater what I do, when the file is opened the error "Multiple circles" is displayed.

All file in this directory behave alike.

However? I can open and simulate any example that come with the simulator.

What can I do?

G.

Show quoted text

From: "helmutsennewald@... [LTspice]"
To: LTspice@...
Sent: Monday, August 1, 2016 5:36 PM
Subject: Re: [LTspice] Re: Looking for a IDT74CBTLV3253 model.

?

Hello Gunoi,

Please take a look to the example file here. It shows how to use the digital devices in LTspice.

DIGITAL_A_DEVICES_1.ASC

?
?
EXAMPLE:
Place an AND
Right mouse click on it.?
A dialog will popup,

SpiceLIne: Vhigh=3.3 Vlow=0 Ref=1.65
SpiceLIne2: Td=1n Trise=1n

This AND has 0V/3.3V output, input threshold 1.65V, delay 1ns, rise and fall time 1n.

Use the nmos4 and pmos4 for the switch. Connect both in parallel as shown in the datasheet's schematic. Connect the substrate of the nmos4 to GND.?Connect the substrate of the pmos4 to VCC(3.3V).

Best regards,
Helmut

Re: No XP?

#90220

Hello Gunoi Nare

You wrote :
"
What I might suggest dough, is to make the new library back compatible with IV. "

"It would be a shame to dismiss the large group of EXpers if they can not use these librarys. "

Why do you think t that? LTspice XVII libraries could not be used with LTspice IV ?
A priori, it has nothing to do with? a new GUI? or a new Spice engine ?
You should ask directly LT ?

Regards
PhB

Re: PMBFJ620/2SK2145 or any other dual JFET-models exist for LTspice?

#90221

I am sorry.
I mistaken.

Bordodynov.

10.08.2016, 08:32, "Александр Бордодынов BordodunovAlex@... [LTspice]" <ltspice@...>:

Show quoted text

Hi.
.MODEL PF5102 NJF(Beta=14.28m Betatce=-500m Rd=1 Rs=1 Lambda=8m Vto=-972.3m Vtotc=-2.5m Is=205.2f Isr=1.988p N=1 Nr=2 Xti=3 Alpha=20.98u Vk=123.7 Cgd=10.76p M=406.9m Pb=1 Fc=500m Cgs=9.56p Kf=0.4931f Af=1)
Digikey $0.81 .

Bordodynov.

10.08.2016, 01:25, "Andy ai.egrps@... [LTspice]" <ltspice@...>:
? ?"Are there sny more around perhaps? Can't seem to find these in any shops."

I don't know what is available to you.? Maybe you should start by finding which dual JFETs you can buy, then look for their SPICE models.

By the way, I easily found SPICE models for a number of dual JFETs, by giving Google a try.? Search term: "dual jfet spice".? Your original question made it sound like you didn't find any.? That would be weird.

Andy

?

Re: Need help to design a transimpedance amplifier

John Woodgate

#90219

开云体育

RE: Layout is critical, the -ve of the opamp has to be point to point with minimum trace length. Most people I've seen have long trace on the -ve input, that is inviting noise pick up. All these has nothing to do with LTspice, it's good common sense EE.

?

This is a *very important general point*, not just for TIAs. ?The minus input of an op-amp has a very low impedance, due to the negative feedback, so it might appear that a long trace is OK, BUT it also has 'infinite' sensitivity, ?Keep the trace as short as possible. If you can't, put a 1 k resistor in series, close up to the op-amp pin. But don't do that if you are using the input as a current sink for an inductive pick-up, so as to get a flat frequency response.

?

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: Wednesday, August 10, 2016 2:54 AM
To: LTspice@...
Subject: [LTspice] Re: Need help to design a transimpedance amplifier

?

It's been 3 days since I posted and still have not shown up.

Regarding to noise pickup like from power supplies, power lines, tv etc. It's very common, any reasonable high transimpedance gain circuit need to have shield to cover the circuit. This kind of noise has nothing to do with the normal noise calculation like voltage and current noise. From my experience, other than the very high speed TIA that has feedback resistor under 1K, all the TIA circuit need to have shield. we just had to relayout a TIA circuit the contractor design that is only 1M feedback resistor. It was picking up noise big time.

For minimum of 200nA signal, that is huge signal, you don't even come close to the voltage and current noise issue. With a 50K feedback resistor, you have 10mV minimum signal. This is big signal!!!

Layout is critical, the -ve of the opamp has to be point to point with minimum trace length. Most people I've seen have long trace on the -ve inpu t, that is inviting noise pick up. All these has nothing to do with LTSpice, it's good common sense EE.

Re: PMBFJ620/2SK2145 or any other dual JFET-models exist for LTspice?

#90218

Hi.
.MODEL PF5102 NJF(Beta=14.28m Betatce=-500m Rd=1 Rs=1 Lambda=8m Vto=-972.3m Vtotc=-2.5m Is=205.2f Isr=1.988p N=1 Nr=2 Xti=3 Alpha=20.98u Vk=123.7 Cgd=10.76p M=406.9m Pb=1 Fc=500m Cgs=9.56p Kf=0.4931f Af=1)
Digikey $0.81 .

Bordodynov.

10.08.2016, 01:25, "Andy ai.egrps@... [LTspice]" <ltspice@...>:

Show quoted text

? ?"Are there sny more around perhaps? Can't seem to find these in any shops."

I don't know what is available to you.? Maybe you should start by finding which dual JFETs you can buy, then look for their SPICE models.

By the way, I easily found SPICE models for a number of dual JFETs, by giving Google a try.? Search term: "dual jfet spice".? Your original question made it sound like you didn't find any.? That would be weird.

Andy

?

Re: No XP?

Gunoi Nare

#90217

Helmut.

Here is a thought.? We, the XPers, or at least me, do not fill the need for a change in GUI.

What I might suggest dough, is to make the new library back compatible with IV.

With the merger of the three companies, there will be enough demand to include the ANALOG and

HITITE in LTC.

It would be a shame to dismiss the large group of EXpers if they can not use these librarys.

Perhaps a GROUP petition to keep these libraries back compatible? would be a good idea.

G

Show quoted text

From: "helmutsennewald@... [LTspice]"
To: LTspice@...
Sent: Tuesday, August 9, 2016 7:20 AM
Subject: [LTspice] Re: No XP?

?

Hello Rick,

The reason is simple.
Mike cannot support XP with the latest Microsoft and Intel compiler tools. These tools only support WIN 7 and newer operating systems.

Best regards,
Helmut

Re: Need help to design a transimpedance amplifier

#90216

This is the article from Burr-Brown that my excel file simulation is based on. If you have problem understanding what I wrote, read this article:

Understanding this, you can then find the relevant numbers from the datasheet and plug into my simulation file and see the total noise.

Re: Need help to design a transimpedance amplifier

#90215

try use the excel simulation file I uploaded a while back and enter in the numbers of your other opamps from the datasheet. If you read through the explanations, they will show you how to enter the numbers into the ones in red color. You can find the numbers from the datasheet. Then you adjust the feedback capacitor Cf+Crf on line 31 to get the 1MHz BW and look at line 47 to 51 for frequency response and inband noise. The total noise is the rms noise. If you shield the circuit properly, you should see the result similar to the number. Remember this is rms noise.

Re: Need help to design a transimpedance amplifier

[email protected]

#90214

Hello All,
Thanks for your response...
Well I have tested almost all inputs in LTSpice as per my design criteria:...it works fine on the screen...

Parameter	Goal
Gain	900 kV / A
V_{out min} (at? 112 nA)	100 mV
V_{out max} (at 5 A)	4.5Vp-p
-3dB Bandwidth	>800 kHz

Parameter

Min

Typical

Max

Unit

Diode Capacitance

(f = 1MHz)

-

0.38

0.5

pF

Reverse Light Current (I )

(Vr = 0.9Vb)

-

10

50

nA

???

??=(V? (???)? ?? (???) ) / ???(???)
???? =4.5?? 0.1?5 μA=880 ?Ω

??? ??≤ ??? ?? ??
??≤ 0.18 pF at 1 MHz pole

???? ≥ (??+?? ) / (?? ?? ???)??? { ??= total capacitance of the photodiode and op-amp (0.5pF + ~ 5pF); }

≥ (? ??+?.???+?.?? ??) / (?????? ???.??^2)
?≥45 ???

Parameter	Required	LTC 6268(FET) [Linear Technology]	OPA354 (CMOS) [Texas Instruments]	AD8066(FET) (Analog Devises)
Supply Voltage	≤ 5V	5V	2.5 V to 5.5 V	5 V to 24 V
Quiescent Current	?	16.5mA	4.9 mA	7.2 mA
Output Voltage Range	0-5V	Rail-to-Rail	Rail-to-Rail	rail-to-rail
Gain-Bandwidth Product	>88 MHz	500 MHz	100-MHz	145 MHz
Input Bias Current	min	4 pA	3 pA	25 pA
Input Offset Current	?	2 pA	±50 pA	10 pA
Input Offset Voltage	min	2.5mV at Vcm = 1V; 4.5mV at Vcm = 2.2V	VS = 5 V, at TA = ?40°C to 125°C ±10mV	2.6 mV
Input Impedance	MΩ ?	>1000 GΩ	10 MΩ	1000 GΩ
Slew Rate	high	400 V/μS	150 V/μS	180 V/μS
Current Noise	min	5.5蹿础/√贬锄	50 fA/√Hz	0.6 fA/√Hz
Voltage Noise	min	4.3苍痴/√贬锄	6.5 nV√Hz	7 nV/√Hz
Input Capacitance	Very min	450 f F	2 pF	2.1 pF

Please correct me if am wrong....

Re: Need help to design a transimpedance amplifier

#90213

It's been 3 days since I posted and still have not shown up.

Regarding to noise pickup like from power supplies, power lines, tv etc. It's very common, any reasonable high transimpedance gain circuit need to have shield to cover the circuit. This kind of noise has nothing to do with the normal noise calculation like voltage and current noise. From my experience, other than the very high speed TIA that has feedback resistor under 1K, all the TIA circuit need to have shield. we just had to relayout a TIA circuit the contractor design that is only 1M feedback resistor. It was picking up noise big time.

For minimum of 200nA signal, that is huge signal, you don't even come close to the voltage and current noise issue. With a 50K feedback resistor, you have 10mV minimum signal. This is big signal!!!

Layout is critical, the -ve of the opamp has to be point to point with minimum trace length. Most people I've seen have long trace on the -ve input, that is inviting noise pick up. All these has nothing to do with LTSpice, it's good common sense EE.

Re: Takes two day for my post to show up

[email protected]

#90212

Some of you seem to be interested in long flaming wars on anything and do't understand the basics of business and how it operates and how acquisitions work. No amount of ?emails would help people who seem to feel they are experts on everything...

Bottom line:

Yahoo as we all knew and may still love will not exist in 1or 2 years.. It is unclear what it will morph into but one thing is for sure... even the meager support will disappear...

Part of being smart is figuring out how to gracefully transition this group to a nore supported and robust platform.. If the majority of you don't feel that we need to do something, then so be it..

Being forewarned is forearmed.

AG

Re: Takes two day for my post to show up

[email protected]

#90211

Some of you seem to be interested in long flaming wars on anything and do't understand the basics of business and how it operates and how acquisitions work. No amount of ?emails would help people who seem to feel they are experts on everything...

Bottom line:

Yahoo as we all knew and may still love will not exist in 1 or 2 years.. It is unclear what it will morph into but one thing is for sure... even the meager support will disappear...

Part of being smart is figuring out how to gracefully transition this group to a nore supported and robust platform.. If the majority of you don't feel that we need to do something, then so be it..

Being forewarned is forearmed.

AG

Re: PMBFJ620/2SK2145 or any other dual JFET-models exist for LTspice?

John Woodgate

#90210

开云体育

Do a web search for UPA63H. I don't know whether it will do what you want.

?

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 9, 2016 6:49 PM
To: LTspice@...
Subject: [LTspice] Re: PMBFJ620/2SK2145 or any other dual JFET-models exist for LTspice?

?

Are there sny more around perhaps? Can't seem to find these in any shops.