Pulling current through a FET while it's turning off

[panfilero]

Hello,

I'm trying to figure out how much current I can pull through a FET while its turning off... basically, how fast I have to turn it off if I have it hooked up to a constant current load so that the load doesn't kill my part while it goes through its resistance region... what information on the datasheet should I be looking at to figure this out?

I'm guessing it's the power dissipation rating, but I'm not sure....


Here's the FET I'm using

http://www.st.com/web/en/resource/technical/document/datasheet/DM00048681.pdf

much thanks!

 

[Joerg]

Hello,

I'm trying to figure out how much current I can pull through a FET
while its turning off... basically, how fast I have to turn it off if
I have it hooked up to a constant current load so that the load
doesn't kill my part while it goes through its resistance region...
what information on the datasheet should I be looking at to figure
this out?

I'm guessing it's the power dissipation rating, but I'm not sure....


Here's the FET I'm using

http://www.st.com/web/en/resource/technical/document/datasheet/DM00048681.pdf

You'll have to keep your eye on figure 2, the safe operating area or
SOA. Make sure you never exceed the limits. For example, while at 200V
Vds it can take 20A for 1mseec, but if it takes 10msec then only 7A.

much thanks!

De nada

 

[Joerg]

You'll have to keep your eye on figure 2, the safe operating area or
SOA. Make sure you never exceed the limits. For example, while at 200V
Vds it can take 20A for 1mseec, but if it takes 10msec then only 7A.

Oh, and that's for single pulse or "once in a blue moon". If such
situations happen in rapid succession you need to also get into figure 3
and avoid death local excessive local heating.

 

[Jamie]

Hello,

I'm trying to figure out how much current I can pull through a FET while its turning off... basically, how fast I have to turn it off if I have it hooked up to a constant current load so that the load doesn't kill my part while it goes through its resistance region... what information on the datasheet should I be looking at to figure this out?

I'm guessing it's the power dissipation rating, but I'm not sure....


Here's the FET I'm using

http://www.st.com/web/en/resource/technical/document/datasheet/DM00048681.pdf

much thanks!

That's a nice part.

to bad the gate cap is so high but I guess it would depend
on the application at hand.

It really depends on your application, I can see that being used in
auto applications incase of load dumps etc.

Personally my self, I wouldn't want a supper fast switching speed, with
high voltage on drain side, the miller effects could prove to be
interesting.

Jamie

 

[Klaus Kragelund]

It is a brute, but the q1 price is $33!

I have 400pcs of this one lying around:

ST STW45NM60 (650V 90mOhm)

http://www.st.com/web/en/resource/technical/document/datasheet/CD00002682.pdf

Anyone want them for a bargain price? (sorry for the sales pitch)

Regards

 

[Guest]

Hello,

I'm trying to figure out how much current I can pull through a FET while its
turning off... basically, how fast I have to turn it off if I have it hooked
up to a constant current load so that the load doesn't kill my part while it
goes through its resistance region... what information on the datasheet
should I be looking at to figure this out?

I'm guessing it's the power dissipation rating, but I'm not sure....


Here's the FET I'm using

http://www.st.com/web/en/resource/technical/document/datasheet/DM00048681.pdf

much thanks!

[email protected]

 

[josephkk]

Hello,

I'm trying to figure out how much current I can pull through a FET whileits turning off... basically, how fast I have to turn it off if I have it hooked up to a constant current load so that the load doesn't kill my part while it goes through its resistance region... what information on the datasheet should I be looking at to figure this out?

I'm guessing it's the power dissipation rating, but I'm not sure....


Here's the FET I'm using

http://www.st.com/web/en/resource/technical/document/datasheet/DM00048681.pdf

much thanks!

That is just not enough information. Where might the current
alternatively go to and what is the compliance of the current source? Is
there any energy transfer capacitors or inductors involved?

?-)