Amplifier schematics for ECW20N20 and ECW20P20

[sercan85]

I have 2 pairs Exicon ECW20N20 and ECW20P20 16A Mosfets. I would like to make an amplifier with them. Could you offer me good desing ?
Thanks

 

[gary s]

Look for many circuits in this thread by member: lineup that use these lateral fets.

 

[gaborbela]

USSA 3 Fab's amplifier....

 

[brian92fs]

Lineup's Ultra allows for ECW20N20 / ECW20P20: Ultra Amplifier with JFET input and Lateral MOSFET out

I designed the PCB's for this and am writing a build guide (just about done). PCB's are available. PM me if interested.

 

[gaborbela]

Do not forget ECW20N20 / ECW20P20 mosfets are dual die.

 

[sercan85]

Lineup’s amplifier works 10n20 and 10p20. 20np20 and 20p20 look different mosfets about input capacitance and load.
That project can be problem about bias with 20n20 and 20p20.
Ussa 3 fab nice but some parts obsolete.

If you have schematics etc i can draw pcb till the 6 layers. And full 3d modeling everythings 😁

 

[UniQ]

Sercan you can use any amplifier design based on Hitachi/Renesas 2SJ50 / 2SK135 in TO3 package or 2SJ162 / 2SK1058 in TO3P package as these FETs are virtually the same, with the exception the 20N* and 20P* have TWO FET dies put into ONE package, just as Garbobela mentioned in post #5... now it's up to you to choose which type of amplifier you want to build, do you like simple and euphonic amp, like this link... or a complex ultra precision amp that feels like an icepick in the ear? :)

 

[sercan85]

When I used the ECW20N20 and 20P20 pair in my Vssa amp. I could not reduce the bias current below 350mA. When I used the 10N20/10P20 pair, the amp worked very stably....
I am afraid that the 20P20/20N20 pair will cause problems in an amp using the K1058/J162 or the 10P20/10N20 pair.
I don't like analytical and clinic sound...when I listened to the LM3886 after 10 minutes headaches, tiredness and sleepiness started...

As a result, I am looking for a suitable amp for my dual die Excicon mos 😀

I'm not a professional electronics guy but I like to deal with this stuff...
https://www.diyaudio.com/community/threads/vssa-lateral-mosfet-amplifier-lazycat-with-exicon.401526/
https://www.diyaudio.com/community/...0-lsk489-composite-feedback-amplifier.413587/
https://www.diyaudio.com/community/threads/approaching-noiselessness-with-the-lt3045.396792/

 

[claudiomas]

at your plac i will do like chevin ,OP TLE2071
résistors R20 R45 value depend on psu voltage for +-15V
on A1500 6K8 5W for +-120V,
and 2200uF in // to each +-15V OP zener

 

[sercan85]

looks interesing... thanks for offer

 

[UniQ]

When I used the ECW20N20 and 20P20 pair in my Vssa amp. I could not reduce the bias current below 350mA

ok that's odd, just to be sure I understood this dilemma, you mean the thermal stability didn't work well below 350mA for these double dies?

 

[sercan85]

@Ultima Thule
No, i dont said it, please just look my vssa project, firstly i builded with 20p20/20n20 and bias couldnt down under 350ma. But vssa works 185ma bias. After i bought 10n20/10p20 it worked good about bias. Maybe this problem only for vssa amp. I dont know. So i have little doubt to use double dies on hitachi or other lateral mosfet applications

 

[UniQ]

What do you expect when putting two FET's in parallel... you MUST double the bias, otherwise they won't reach the negative temp co, everything is in the datasheet.

edit: attached below the tempco graph for single VS double die.

 

[BrianGasberg]

I would look at tombos here:
https://www.diyaudio.com/community/...te-low-power-class-a-amplifier-my-way.404147/

 

[sercan85]

What do you expect when putting two FET's in parallel... you MUST double the bias, otherwise they won't reach the negative temp co, everything is in the datasheet.

edit: attached below the tempco graph for single VS double die.
View attachment 1356805 View attachment 1356806

Thanks for attention. Yes i saw it and i understand good now…

 

[sercan85]

I would look at tombos here:
https://www.diyaudio.com/community/...te-low-power-class-a-amplifier-my-way.404147/

Thanks for advice Yes i read all pages… i can try but i want to little more power 🔥

 

[russel]

at your plac i will do like chevin ,OP TLE2071
résistors R20 R45 value depend on psu voltage for +-15V
on A1500 6K8 5W for +-120V,
and 2200uF in // to each +-15V OP zener

That looks similar to the musical fidelity P170/P270 ... series. I have done a pcb, this is the latest vaersion. If you want the kicad files let me know and I will post them up. The op-amp 5534 should really be an opa134 or better an opa604 if you have one ,which is what I used. 5534 has to high input bias current for this circuit.

 

[sercan85]

Thanks for advice @russel
I have to admit, I dont want to build opamp based amplifier nowadays. Maybe we can try ECW20N20/20P20 in @Nico Ras 's amplifier, or he can offer the others options. I asked how many mA the bias current is for this amp, I hope he answers.

 

[ostripper]

I wanna try something like this -
Very reliable , most of these old amps are still working. Just a re-cap after 40+ years.
I'd run Toshiba TTA/C004's for the VAS @ 6-8mA to drive the FET's.

 

[sercan85]

Maybe we need to touch zener diodes on LTP too.. What is this amplifier's model?