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Bought some cheap 30N60's, genuine or fake?

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Wolfram

Tue Jan 24 2012, 12:56AM

Registered Member #33 Joined: Sat Feb 04 2006, 01:31PM
Location: Norway
Posts: 971

Wow, I did not expect that. I guess I have to be careful if I buy IGBTs on eBay. Any other part numbers known to be affected?

I wonder what part number these really are.

Edit: I just found this

,%20a%20problem%20difficult%20to%20be%20solved% 20(ENG).pdf interesting document with some pictures and info on a different fake IGBT.

Edit2: Fixed link that had become dead

Patrick

Tue Jan 24 2012, 06:46AM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

I have about 70 of the 7's and 30's in question, however mine were sourced through Mouser, at the quoted price, with no suspicous tells.

i never seen any Transistor bodies with that kind of graining, below, that looks like belt graining on a plate.(which i used to do, when we had a bad dross edge on lased stainless steel.)

Also perhaps the legitamet makers should include a step-staircase or diagonal on the left and right. so any grinding
(loss of hieght) would be apparent.

Dr. Dark Current wrote ...

I bought a lot of HGTG30N60A4D IGBTs from one ebay seller. The parts do not look very genuine to me. The

Anyone caught changing part marks should have thier face chopped off....
cowards i say!

If this were to be used on a 747, with 300 people on board......

Dr. Dark Current

Tue Jan 24 2012, 10:22AM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

So I just murdered one with a hammer... To my surprise, the chip dimensions look like the real part !! I'm puzzled... The IGBT itself is 6.5x6.5 mm and the diode is 2.5x5 mm.

What does this mean? Could it be a slower IGBT (eg. a 30N60C3D) relabelled as A4D? I don't know... Probably not because the slower parts also have less power dissipation so smaller chips.

Patrick

Tue Jan 24 2012, 12:28PM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

maybe you should scope the rise and fall times. also your other pics seem to indicate the mold circles in some are missing.

Dr. Dark Current

Tue Jan 24 2012, 04:02PM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

Forward voltage and reverse diode voltage characteristics. The IGBT was mounted on a moderately sized heatsink with a fair amount of heat paste. The test was carried out quickly (less than 10 sec) so the heatsink stayed at room temp. The junction temperature did rise a bit of course but this is out of my control.

Gate charge measurement. The "reference" transistor is the FGH40N120AN with 220 nC gate charge. The fake 30N60A4D seems to have similar gate charge. The datasheet value is 225 nC, so this seems fine. The test was done with C-E shorted.

Then I tried to measure the fall time, but I failed. The scope just picks up too much ringing... This possibly can't be due to parasitic inductances in the circuit because all is kept very short. Anyway, I'll post the results. Any ideas?

Test circuit:

1327420626 152 FT132967 Test Circuit Swtimes

The approximate values for the test were Ic = 10 A, Vce = 17 V.

Dr. Drone

Tue Jan 24 2012, 04:30PM

Registered Member #290 Joined: Mon Mar 06 2006, 08:24PM
Location:
Posts: 1673

Dr. Dark Current

Tue Jan 24 2012, 06:58PM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

Dr. Spark, sadly most of the die was damaged and I don't want to destroy another part...

Here's a slightly better voltage fall time measurement. I can't get the current fall time measurement to work acceptably though...

The current turn-off delay time seems to be around 100ns for 10A. According to the datasheet, it should be around 140ns. All the measurements suggest that this is a genuine part... I don't know.

Edit: I just realised that the value in the datasheet is given for Vce of 390V and in my case its just 20V.

Dr. Drone

Tue Jan 24 2012, 07:42PM

Registered Member #290 Joined: Mon Mar 06 2006, 08:24PM
Location:
Posts: 1673

Tetris

Wed Jan 25 2012, 04:14PM

Registered Member #4016 Joined: Thu Jul 21 2011, 01:52AM
Location: Gainesville, FL
Posts: 660

It can't be as bad as RadioShack crap hee hee :P Radioshack stuff breaks within a few minutes!

Forty

Wed Jan 25 2012, 05:39PM

Registered Member #3888 Joined: Sun May 15 2011, 09:50PM
Location: Erie, PA
Posts: 649

why does red fuming nitric dissolve the plastic and not the die, but if i put an IC into concentrated 70% (not fuming I guess) nitric acid it dissolves the insides out through the pin holes and leaves the shell unharmed?

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