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.
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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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.
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.
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)
.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)
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.
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.
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.
Hi,
yes i saw that , the parameters seem too much optimistic
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 .
The models Bob Cordell has on his site are excellent (goto spice and models in top header)
CordellAudio.com - Home
CordellAudio.com - Home
yes, but these models are not there, and there are questions about a number of models
First cycle distortion - Graham, what is that?
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