2SA1145 Ltspice model

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
It took me ages to sus out using models too :)

Here's what you do.

1) Copy the entire text of the two models (from the post djoffe linked too)

2) Paste the text into notepad and name and save it. (call it anything such as My Models)

3) Move the notepad file into the same folder as the .asc file you want to use it with. (LTspice by default saves .asc to the program directory files where the program resides. I find that inconvenient and always save files to "Documents")

4) Open your .asc file as normal with LTspice and add the directive .include My Models.txt (don't miss the dot out or the .txt)

5) Now go over the transistor you want to replace and right click the device type (not its reference number). So if you have a 2N2904 showing you right click the 2N2904 and replace the text with 2SA1145 or 2SC2705

If you get stuck ask :) As I say, it took me weeks to sus all this out as a lot of knowledge is assumed.
 
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manso

Member
2013-01-26 9:57 pm
First take a good look at those models ;)

They are absolutely useless. From device capacitance to hfe to early voltage and Ft. Dont waste your time and be fooled by the results this will provide.
At least some models floating around on the net get at least one aspect correct, these models have everything wrong. :eek:
 
Are these any better?
.model Q2sa1145 PNP(Is=67.34f Xti=3 Eg=1.11 Vaf=100 Bf=152.4 Ise=67.34f
+ Ne=1.396 Ikf=.5 Nk=1.913 Xtb=1.5 Var=100 Br=1 Isc=314.9f
+ Nc=1.082 Ikr=6.118 Rc=3.162 Cjc=6.536p Mjc=.3434 Vjc=.6025
+ Fc=.5 Cje=5p Mje=.3333 Vje=.75 Tr=10n Tf=833.2p Itf=5.198
+ Xtf=644 Vtf=10)
.model Q2sc2705 NPN(Is=14.91f Xti=3 Eg=1.11 Vaf=100 Bf=145.1 Ise=14.91f
+ Ne=1.349 Ikf=.4991 Nk=1.726 Xtb=1.5 Var=100 Br=3.184 Isc=343.9p
+ Nc=1.85 Ikr=19.54m Rc=0 Cjc=4.636p Mjc=.2807 Vjc=.3905 Fc=.5
+ Cje=5p Mje=.3333 Vje=.75 Tr=10n Tf=1.062n Itf=67.89 Xtf=16.27n
+ Vtf=10)
 

manso

Member
2013-01-26 9:57 pm
Much better yes, these at least start giving some resemblence of the excellent performance of these parts.

Hfe looks realistic, early voltage about correct, device capacitances still a bit too high but at least these will provide more realistic results.

I have models of these transistors too, will post them tomorrow.
 

lainarko

Member
2013-05-06 8:24 am
First take a good look at those models ;)

They are absolutely useless. From device capacitance to hfe to early voltage and Ft. Dont waste your time and be fooled by the results this will provide.
At least some models floating around on the net get at least one aspect correct, these models have everything wrong. :eek:


Hi,

yes i saw that , the parameters seem too much optimistic :p
 

lainarko

Member
2013-05-06 8:24 am
Much better yes, these at least start giving some resemblence of the excellent performance of these parts.

Hfe looks realistic, early voltage about correct, device capacitances still a bit too high but at least these will provide more realistic results.

I have models of these transistors too, will post them tomorrow.


ok thanks i'm waiting for them so ;)

thanks to everyone for the help , i really appreciate .
i'm starting to make an hybrid tube/transistor headphone amp , and i will try to use components that best sound .
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
It was nearly 8 years ago I posted that link but it still seems to work. My reply was just a follow on to the comments about 'useless models' and suggesting those of Bob's were pretty good.

It wasn't meant to say that those specific devices were on the list.