Fake BD139/140 ?

[altec9440]

I was given a lot of BD139/140

Transistors have no metallic plate like TO126, all sides are isolated. The thickness is 3.3 vs 2.6mm. Caracteristics (vbr, hfe) are just above datasheet listing.

I already saw this isolated package but I didn't found any reference of this in fairchild datasheet for 139/140.

fake or not ?

 

[JMFahey]

No economic incentive in faking such cheap and available transistors, so *maybe* you got a different isolated package but no big deal.

IF they meet specs, why not use them?

 

[ohdsp]

Would agree these are too cheap to fake, but you never know with some people, they will try anything on...

However I also have some similar parts, fully isolated package, datasheet stated somewhere that the package does not comply to any existing package standards.

Actually find them really useful, no mica washers or sil-pads needed, just a dab of silicon grease. Probably wouldn't use them anywhere that they run really hot though...

 

[dreamth]

nothing to worry about...Fairchild , JRC, ON semiconductor...they all adopted this new type of heatsink long time ago.They are good enough ...

 

[Elvee]

Anything can be faked, even cheap BD's, but an isolated case version is completely normal. Generally, it is indicated by a "F" suffix.

 

[altec9440]

thanks fellows for good news. I have enough fakes for led supply !

 

[Elvee]

If you send me one sample, I can characterize most of its characteristics: Ft, Early voltage, die volume, etc
This will help you decide what to do with your stock

 

[altec9440]

Testing knowledge (and equipment) that missing to me. Thanks for proposition. pm sent

 

[schillg11]

The solution of this question can be found here
https://www.mouser.de/datasheet/2/308/BD139-D-1802507.pdf

 

[wg_ski]

The newer ON/Fairchild BD139 don’t look anything like the old Philips type from Yesteryear. If you do compare curves it will look different, but it will work in any place an old BD139 will. Isolated case is the new normal for the TO-126 - the Jap manufacturers started doing it first and it seems to have finally caught on, about the time ON acquired those old Sanyo parts (most of which are discontinued now). ST still makes non-isolated TO-126, but is in the process of dropping all those types.

 

[thimios]

Looking at the two images in the first post. Picture in the right is a genuine part, Fairchild manufacture.
I can't recognise the manufacture in the left, maybe fake.
Yes i see fake parts all over the world..cheap fake too.

 

[altec9440]

cooling performance non-isolated vs isolated differ... Time to stock metal parts ?