---
+ Post New Thread
Page 1 of 2 12 LastLast
Results 1 to 20 of 30
  1. #1
    boy
    boy is offline
    Advanced Member level 1
    Points: 9,590, Level: 23
    boy's Avatar
    Join Date
    Sep 2002
    Location
    Thailand
    Posts
    483
    Helped
    92 / 92
    Points
    9,590
    Level
    23

    atf36077 model zap file

    I have simulate the FET in ADS by using the nonlinear model provided by agilent for LNA (The Gaas FET is ATF54143). The s-parameter from the simulation does not agee well with the measurement s-parameters. I have some doubt about the nonlinear model. how it accurate? In the agilent application note, they use the measured s-parameter for design. Can I conclude that.

    1. for small signal amp. LNA -> measured s-parameter is the best.

    But how about P1, IP3? can i still use the nonlinear model to predict them?

    2. for oscilator, VCO -> I think i still can use measured s-parameter for open loop analysis but I do need a nonlinear model for transient and HB to predict the harmornic and start up. ALso most nonlinear model does not provide the phase noise parameters so it renders the phase noise simulation useless.

    3. PA .. I think only load pull work. I dont think any large signal model will work because the environment for parameter extraction is not same as the real environment (i.e. mechanical construction, heat sink, etc.)

    I am very frustrated for the nonlinear model. even the V-I curve does not agree well with the data sheet. The model is Curtice 2. (I am frustrated becuase i am using Agilent simulator, Agilent FET and Agilent model, it still does not accurate how can I trust other vender model (such as CEL) )

    Any experience which model will be used in what kind of design???

  2. #2
    Full Member level 2
    Points: 3,898, Level: 14
    gecky's Avatar
    Join Date
    Aug 2004
    Posts
    127
    Helped
    6 / 6
    Points
    3,898
    Level
    14

    atf-54143 spice

    Hi Boy,

    I face the same problem as you... I'm using a NEC (CEL) FET. But at least Agilent datasheet provides the parameters used in the nonlinear model, the NEC datasheet I have don't and I'm clueless what they used!

    I'm not too sure but you can try to optimise the parameters you have by looking at the ADS tutorial under : example\MW_cct\AModelB..
    It'll fit the parameters to the measured results you have I suppose.



    •   Alt6th January 2005, 01:16

      advertising

        
       

  3. #3
    boy
    boy is offline
    Advanced Member level 1
    Points: 9,590, Level: 23
    boy's Avatar
    Join Date
    Sep 2002
    Location
    Thailand
    Posts
    483
    Helped
    92 / 92
    Points
    9,590
    Level
    23

    fet model

    Dear gecky
    Thank you, i will try. some CEL data sheet give you the value of all parameters. But if you look carefully, AF and KF will be 0 and 1 respectively, so we cannot simulate phase noise. only few CEL FET which they recommend for OSC design, provide AF and KF. Have you ever use NE3210S01 in any design, i need to know how accurate the model is?



  4. #4
    Advanced Member level 2
    Points: 8,548, Level: 22
    abdoeng's Avatar
    Join Date
    Feb 2004
    Posts
    648
    Helped
    69 / 69
    Points
    8,548
    Level
    22

    s parameter fet

    hi all,most of person here say to use s parameter model that is more accurate than nonlinear model,.i use s par. model in my design
    that all
    regards



  5. #5
    Full Member level 2
    Points: 3,898, Level: 14
    gecky's Avatar
    Join Date
    Aug 2004
    Posts
    127
    Helped
    6 / 6
    Points
    3,898
    Level
    14

    jfet osc designs

    Hi abdoeng,

    like in your reply to one of my posts, we need Harmonic Balance to ensure there is steady state osc. The S-para model can't be used for this. May I know how you design oscillators? Or all just depends on the accuracy of the nonlinear model?

    Thanks!



  6. #6
    Advanced Member level 2
    Points: 8,548, Level: 22
    abdoeng's Avatar
    Join Date
    Feb 2004
    Posts
    648
    Helped
    69 / 69
    Points
    8,548
    Level
    22

    ads sp pb model fet

    Quote Originally Posted by gecky
    Hi abdoeng,

    like in your reply to one of my posts, we need Harmonic Balance to ensure there is steady state osc. The S-para model can't be used for this. May I know how you design oscillators? Or all just depends on the accuracy of the nonlinear model?

    Thanks!
    hi gecky,i only design lna ,i will sonner in sha'a *****,design oscillator,i use s par. model in the lna design,hee the results



  7. #7
    Advanced Member level 5
    Points: 15,234, Level: 29
    khouly's Avatar
    Join Date
    Oct 2003
    Location
    EGYPT
    Posts
    2,371
    Helped
    443 / 443
    Points
    15,234
    Level
    29

    ne3210s01 1db compression

    even in LNA design u need also acurate nonlinear model . to simulate the nonlinearity of the amp
    like 1 dB compression point and IIP3
    it is a very important specs of the desgin

    both models r important

    thanks



  8. #8
    boy
    boy is offline
    Advanced Member level 1
    Points: 9,590, Level: 23
    boy's Avatar
    Join Date
    Sep 2002
    Location
    Thailand
    Posts
    483
    Helped
    92 / 92
    Points
    9,590
    Level
    23

    sparameters of fet

    But the nolinear model is not agree with measured s-parameter model. I have simulate to get the s-parameter table from the non-linear model and compare it to the one in the data sheet. It does not aree well, that is the problem.



    •   Alt6th January 2005, 23:12

      advertising

        
       

  9. #9
    Full Member level 1
    Points: 2,629, Level: 11
    zeshan102's Avatar
    Join Date
    May 2003
    Location
    Heart of Pakistan
    Posts
    100
    Helped
    9 / 9
    Points
    2,629
    Level
    11

    atf-54143 curtice ads model edaboard

    if u r biasing the FET according to the data sheet nonlinear model give same s-parameter check your id and vds it shoud be similar as given in s parameter model.



    •   Alt8th January 2005, 06:00

      advertising

        
       

  10. #10
    Full Member level 2
    Points: 3,898, Level: 14
    gecky's Avatar
    Join Date
    Aug 2004
    Posts
    127
    Helped
    6 / 6
    Points
    3,898
    Level
    14

    nonlinear model

    if u r biasing the FET according to the data sheet nonlinear model give same s-parameter check your id and vds it shoud be similar as given in s parameter model.
    Hi,

    like boy, I face the same problem... I'm using NE76184A.... checked Vds and Ids and they are as per those for S-para in the datasheet.

    Both the nonlinear and S-para model for this FET is available in ADS. You can try and see if you can get it to work. Thanks!



  11. #11
    boy
    boy is offline
    Advanced Member level 1
    Points: 9,590, Level: 23
    boy's Avatar
    Join Date
    Sep 2002
    Location
    Thailand
    Posts
    483
    Helped
    92 / 92
    Points
    9,590
    Level
    23

    spice s-parameter model connection

    dear zeshan102
    I have check by DC simulation. it is 100% sure that VD and Id is same as in the data sheet.

    Dear
    GeckyI will give it a try and let u know.



  12. #12
    Newbie level 5
    Points: 1,506, Level: 8

    Join Date
    Dec 2004
    Posts
    10
    Helped
    0 / 0
    Points
    1,506
    Level
    8

    ads fet models

    Agilent suplies some nolinear modals,you can get it throught its web sit!



  13. #13
    Full Member level 2
    Points: 3,898, Level: 14
    gecky's Avatar
    Join Date
    Aug 2004
    Posts
    127
    Helped
    6 / 6
    Points
    3,898
    Level
    14

    ads model hemt

    summersonic,

    the problem Boy and myself face is that the nonlinear model provided by ADS give very different performance from the datasheet small-sig S. So we are questioning the accuracy/validlity of using these models... but on the other hand, we are left with no choice (for myself at least) because I'm designing an oscillator and the nonlinear model is required. Will be good if you can share your experience with us :)

    Thanks!



  14. #14
    Newbie level 5
    Points: 1,593, Level: 9

    Join Date
    Jun 2004
    Posts
    10
    Helped
    0 / 0
    Points
    1,593
    Level
    9

    osc paramodel

    Hi all,
    I need nonlinear model of ATF26884 and ATF 36077 from @gilent and NE321S01 from N-E-C. I need this models for simulating VCO at 11GHz . Where to download this ?
    Does anybody have measured s-par of this transistors?Are measured s-pars same as s-pars from manufacturers?



  15. #15
    Advanced Member level 5
    Points: 15,234, Level: 29
    khouly's Avatar
    Join Date
    Oct 2003
    Location
    EGYPT
    Posts
    2,371
    Helped
    443 / 443
    Points
    15,234
    Level
    29

    s2p file ne3210s01

    u can find the nonlinear model of NE3201so1
    www.cel.com
    there is a design kit for @DS download it and there r many nonlinear models



  16. #16
    Full Member level 2
    Points: 2,364, Level: 11

    Join Date
    Dec 2004
    Location
    China
    Posts
    128
    Helped
    7 / 7
    Points
    2,364
    Level
    11

    ads fet model parameters

    I am expecting someone can totally solve these problems in the above .
    Thanks !



  17. #17
    Advanced Member level 2
    Points: 8,548, Level: 22
    abdoeng's Avatar
    Join Date
    Feb 2004
    Posts
    648
    Helped
    69 / 69
    Points
    8,548
    Level
    22

    gaas fet spice model

    Quote Originally Posted by zeshan102
    if u r biasing the FET according to the data sheet nonlinear model give same s-parameter check your id and vds it shoud be similar as given in s parameter model.
    hi i not agree with u that i try to simulate nonlinear with biasing of datasheet and very differ from the linear spar module,u know why?

    Added after 6 minutes:

    Quote Originally Posted by sini
    Hi all,
    I need nonlinear model of ATF26884 and ATF 36077 from @gilent and NE321S01 from N-E-C. I need this models for simulating VCO at 11GHz . Where to download this ?
    Does anybody have measured s-par of this transistors?Are measured s-pars same as s-pars from manufacturers?
    hi sini,i use atf36077 but at linear mode at design of lna,are u want its datasheet i can upload
    what about u osc.design



  18. #18
    Advanced Member level 5
    Points: 15,234, Level: 29
    khouly's Avatar
    Join Date
    Oct 2003
    Location
    EGYPT
    Posts
    2,371
    Helped
    443 / 443
    Points
    15,234
    Level
    29

    ads fet model

    Dear all

    i am using AT32033 in design of LNA and oscillator , and i need to know how accurate the sparameter file contianed in @DS also i need to know the nonlinear model in @DS or not

    thanks



  19. #19
    boy
    boy is offline
    Advanced Member level 1
    Points: 9,590, Level: 23
    boy's Avatar
    Join Date
    Sep 2002
    Location
    Thailand
    Posts
    483
    Helped
    92 / 92
    Points
    9,590
    Level
    23

    cel fet nonlinear models

    http://www.home.agilent.com/cgi-bin/...arch_for_go=Go

    There ia a spice model there. U cal try to import the spice model to ADS and compare it with the measured S-parameter (also can be download from the site in s2p format) Also the agilent always mention

    "While models in this library reflect close similarity to device performance, simulation is only a supplement to lab evaluation. Model performance in general will reflect typical specs for a device, but some aspects of performance may not be modeled fully. Care has been taken in their preparation, however, we cannot be responsible for correct application on any and all computer systems. Agilent Technologies reserves the right to improve these models without prior notice. Refer to the datasheet for guaranteed performance and design guidelines."

    it means that you use it at your own risk.



  20. #20
    Advanced Member level 2
    Points: 8,548, Level: 22
    abdoeng's Avatar
    Join Date
    Feb 2004
    Posts
    648
    Helped
    69 / 69
    Points
    8,548
    Level
    22

    ne3210s01 ads

    hi,all,thanks all for care,but i ignore how to import spice file to ads,
    pls tell me how,that i am new in using ads2003a
    regards
    i use atf36077 ,here its



+ Post New Thread
Please login
Page 1 of 2 12 LastLast