2N series Fets like 2SK246/ 2SJ103 ? - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 30th May 2006, 10:34 AM   #1
diyAudio Member
 
ashok's Avatar
 
Join Date: Jun 2002
Location: 3RS
Default 2N series Fets like 2SK246/ 2SJ103 ?

Since I cannot find Spice data for 2SK246 and 2SJ103 , I assume if there are 'similar' small signal FET's like these in the 2N range or some other series , their Spice models will be more easily available. They must be complementary devices.
Thanks.
Cheers.
__________________
AM
  Reply With Quote
Old 30th May 2006, 11:18 AM   #2
Netlist is offline Netlist  Belgium
diyAudio Moderator Emeritus
 
Netlist's Avatar
 
Join Date: Jan 2003
You've got mail.

/Hugo
  Reply With Quote
Old 30th May 2006, 11:23 AM   #3
diyAudio Member
 
ashok's Avatar
 
Join Date: Jun 2002
Location: 3RS
Thanks Hugo .
Ashok.
__________________
AM
  Reply With Quote
Old 1st June 2006, 10:03 AM   #4
diyAudio Member
 
Join Date: Mar 2004
Location: Krakow
Quote:
Originally posted by Netlist
You've got mail.

/Hugo

Hugo,
may I ask one too?
Thank you in advance!
__________________
regards, Pawel
  Reply With Quote
Old 16th July 2007, 11:58 PM   #5
diyAudio Member
 
davygrvy's Avatar
 
Join Date: Mar 2007
Location: Oakland, CA
Blog Entries: 1
Could I get a copy of the SPICE models for the 2SK246BL and 2SJ103BL, too?
  Reply With Quote
Old 2nd June 2008, 10:33 PM   #6
juma is offline juma  Germany
diyAudio Member
 
juma's Avatar
 
Join Date: Nov 2005
Location: Berlin
Can you please send me spice models for 2SK246 and 2SJ103 ?
Thanks a lot !
  Reply With Quote
Old 3rd June 2008, 06:53 AM   #7
diyAudio Member
 
Join Date: Jun 2007
From the Orcad libraries:

Quote:
.model J2sk246 NJF(Beta=1.07m Rs=56.76 Rd=56.76 Betatce=-.5 Lambda=2.8m
+ Vto=-2.638 Vtotc=-2.5m Cgd=10.38p M=.4373 Pb=.3905 Fc=.5
+ Cgs=6.043p Isr=112.8p Nr=2 Is=11.28p N=1 Xti=3 Alpha=10u Vk=100
+ Kf=1E-18 Af=1)
Quote:
.model J2sj103 PJF(Beta=2.197m Rs=76.76 Rd=76.76 Betatce=-.5 Lambda=735.3u
+ Vto=-2.037 Vtotc=-2.5m Cgd=18.95p M=.5045 Pb=.3905 Fc=.5
+ Cgs=17.02p Isr=38.48f Nr=2 Is=3.848f N=1 Xti=3 Alpha=10u Vk=100
+ Kf=1E-18 Af=1)
  Reply With Quote
Old 3rd June 2008, 07:36 AM   #8
diyAudio Member
 
Join Date: Sep 2007
Send a message via Yahoo to linuxguru
Just out of curiousity - apart from the Vds rating of 50V, in what way is the 2sk246 superior to say, the BF245c or similar?
  Reply With Quote
Old 3rd June 2008, 10:06 AM   #9
lineup is offline lineup  Sweden
diyAudio Member
 
lineup's Avatar
 
Join Date: Dec 2005
Location: the north
Quote:
Originally posted by linuxguru
Just out of curiousity - apart from the Vds rating of 50V,
in what way is the 2sk246 superior to say, the BF245c or similar?
I would not say 2SK246 or any JFET is superior, to another.
It all comes down to what specific job you want your JFET to do.


And this is what makes a good audio amplifier designer:

1. Knowledge about different components.
This is one of the most fundamental thing.
How they behave in different circuits and
what good features and limitations any component has.

We see often Nelson Pass and other world class amplifier designers
use the same transistors over and over again.
This is not necessarily because they are the best HEXFET.
But Nelson Pass knows these ( IRF240, IRF9240, IRF610, IRF9610 )
like his own backpocket.
This is why he can get them perform 99.9% time after time.

When he wants to use some hypermodern, like LU1010 power JFET,
he needs to spend time experimenting, testing, to get knowledge and be familiar with the new ones.
If not, he will not be able to get more than 70-80% out of these,
however much better they are, than older devices.

2. The ability to set up good working environment in circuit.
With currents, voltages, that suits the components chosen as optimal as possible.

And arrange them all, so they work 'perfectly' together.

------------------------------------------


Speaking of 3 common JFETs.
Quote:
BF245 - 30 Volt
JFET VHF/UHF Amplifiers
http://www.onsemi.com/pub_link/Collateral/BF245A-D.PDF

2SK246 - 50 Volt
For Constant Current, Impedance
Converter and DC-AC High Input
Impedance Amplifier Circuit Applications
http://www.ampslab.com/PDF/2sk246.pdf

2SK170 - 40 Volt
Low Noise Audio Amplifier Applications

Recommended for first stages of EQ and M.C. head amplifiers.
http://www.semicon.toshiba.co.jp/doc...eet_071101.pdf
The limiting factor for JFET is often Max Voltage and sometimes Max Current ( IDSS ).
Aside from BF245 is 'only' 30 Volt, you see it is mainly for VHF/UHF use.
RADIO frequencies, while audio is AF, LF. Lower frequency.
Nevertheless, BF245 can be used for current sources in audio amplifiers.
To serve the other transistors. BF245 is not a bad transistor.

2SK246 has an attractive feature ( like the PFET 2SJ103 ).
It can take 10 Volt higher, than 2SK170.

Finally, 2SK170.
2SK170 - 40 Volt
Low Noise Audio Amplifier Applications
Recommended for first stages of EQ and M.C. head amplifiers.


... there is no need to comment on that, is there
It is no coincidence 2Sk170 is very popular in Audio Amplifiers.
Fairly high voltage, 40 V, but most of all low noise and
it is recommended by Toshiba for demanding audio amplifiers.
MC Phono RIAA, for example.


Regards - lineup
__________________
lineup
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Three 10" 4Ohm subs, wired in series or series-parallel? Nagamitsu Car Audio 38 19th February 2014 11:16 PM
Quality of Hammond 300 series power transformers compared to 200 series? G Tubes / Valves 10 3rd August 2012 07:32 AM
Yamaha CA-series / CT-series parts DragonMaster Parts 9 19th January 2007 07:48 PM
substituting FETs elementx Solid State 6 5th December 2006 03:40 PM
Aleph 5 with other FETs ??? 2SK series Adrie Pass Labs 2 24th January 2005 07:44 AM


New To Site? Need Help?

All times are GMT. The time now is 08:01 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2