Most Greedy Boy, of them all... or (there is no) DEFiSIT of Papa's Koans

[Chul]

I inserted 2-ohm resistor between two Sources and the voltage is closer the center.
What is the target here? What am I doing?

 

[generg]

between FET and output .... but better try both yes more than two 1R parallel I would no use.

You had a good eye with the IRFP150 for a possible match.

You have no friend with a curvetracer to test your IRFP150?

 

[generg]

I inserted 2-ohm resistor between two Sources and the voltage is closer the center.
What is the target here? What am I doing?

2 Ohm is fairly high, it will limit your current too much.

I am afraid you must look for brothers of your first IRFP150.

 

[Chul]

Hi genard, unfortunately no one around to help me with that.
I have some measuring equipment that I do not even know the name, somewhere in the storage. I hope I can ask people how to use them someday.

I wanted to try IRFP9240 but I do not have them and I found IRFP150N, thus I tried the 2SJ28 that was left from the use of 2SK82. It is just a random pick up and trial.
Do you mean the resistor bigger than 1 ohm is not recommended? With 2 ohms Vds of IRFP150N is now 10V or so..

 

[generg]

and your current?

 

[Chul]

Current was 1.5A the same.

I increased the B+ to 30V and it is similar. 1.5A, FET Vds 10V. FET Vgs 4.1V.
Maybe I should try other FETs, IRFP240, 250, 260..

 

[generg]

Do you have more P SITs?

this one way there might be one better fitting... but best is to measure them.

Or you try all your IRFP150 and look for a brother of the first one.

 

[Chul]

Do you have more P SITs?

this one way there might be one better fitting... but best is to measure them.

Or you try all your IRFP150 and look for a brother of the first one.

Yes in fact I have some including 2SK82 and 2Sk180, THF51-S. Even I can see that the variation is high. they make sound but far from consistent.

You mean P SIT have more candidate N FETs? If so I think I can try them..

 

[generg]

you need a SIT with around 4.5V at 1.5A and the same for the P channel.

Look that is/was my SITuation...

Black the N-SITs red the P channels.

 

[Chul]

I have those THF51 and 2SK182ES. I checked the Vgs at some fixed Vds and Id. Could you have a look and give me a tip on which one to begin with FET choice?

I am on my way home now and I will show what checked soon.

 

[generg]

In theory it works a bit....but look at the biasing voltage....hu hu

:--))

 

[ggetzoff]

MKC is MKC is MKC

just use what you have

 

[Chul]

you need a SIT with around 4.5V at 1.5A and the same for the P channel.

Look that is/was my SITuation...

Black the N-SITs red the P channels.

What was your choice with that?

Attached is what I have..

 

[generg]

I would say all your parts situated between 4.5 and 5V at 2A are worth a try!

Maybe another comment would be helpful!

 

[Zen Mod]

from whom?

 

[Chul]

Mighty ZM I think you are as bad as Nelson..
But your input is welcome ;-)

 

[Zen Mod]

one thing I'm constantly forgetting to investigate (going through catalogs , then being distracted with something else) ;

IRFP150 is , say , as two IRFP240 in one case

is there some counterpart ( two IRFP9240 in one case ) in P polarity ...... ?

of course - easily available , and cheap ......

 

[generg]

What was your choice with that?

Attached is what I have..

besides the choice problem, you are a happy guy....so many SITs in one place.

Heaven!

 

[Zen Mod]

Mighty ZM I think you are as bad as Nelson..
But your input is welcome ;-)

couldn't add anything to what meine älterer Bruder already wrote

besides , you both have more experience with these funny looking parts than me ...... having them in vivo , with curve tracer and all

 

[lhquam]

one thing I'm constantly forgetting to investigate (going through catalogs , then being distracted with something else) ;

IRFP150 is , say , as two IRFP240 in one case

is there some counterpart ( two IRFP9240 in one case ) in P polarity ...... ?

of course - easily available , and cheap ......

Maybe IXTH26P20P.