BF862 spice model problem? - 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 7th August 2014, 08:17 AM   #1
udok is offline udok  Austria
diyAudio Member
 
Join Date: Jul 2011
Default BF862 spice model problem?

Have you tested the NXP spice model for BF862?

The curves do not match the datasheet...
And worse: This is the first JFET with gate current in the uA range...

Any ideas?
Attached Images
File Type: jpg BF862_ID_Plot.jpg (197.9 KB, 35 views)
File Type: jpg F862_GateCurrent.jpg (200.4 KB, 35 views)

Last edited by udok; 7th August 2014 at 12:10 PM.
  Reply With Quote
Old 7th August 2014, 12:23 PM   #2
udok is offline udok  Austria
diyAudio Member
 
Join Date: Jul 2011
I modified the spice model to better fit the typical datasheet characteristics.
Ignoring the temperature parameters solves the problem
with the gate input current.

Model appended:
*
* MODIFIED BF862 SPICE MODEL 7.8.2014
*
.MODEL BF862U NJF
+ VTO = -0.75
+ BETA = 0.033
+ LAMBDA = 0.033
+ RD = 0.8
+ RS = 7.0
+ CGS = 8p
+ CGD = 7.5p
+ PB = 0.5
+ FC = 0.5
+ KF = 87.5E-18
+ AF = 1
+ M = 0.6
*
  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
Spice model for GU50 (LT-Spice) voltagezone Tubes / Valves 44 19th November 2013 08:05 AM
opa627 Spice Model vs Ideal Opamp Model HiFiNutNut Chip Amps 7 16th September 2013 10:40 PM
Tube Spice Model Problem valveitude Tubes / Valves 5 5th July 2005 01:56 AM
SPICE model Prune Parts 6 16th October 2004 03:22 PM
Spice model doigtee Tubes / Valves 6 12th July 2003 11:42 AM


New To Site? Need Help?

All times are GMT. The time now is 04:07 AM.


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