ENEDED

Thank you for the suggestion.

I’ll run the thermal test tonight. I have an IR thermometer and I’ll be using fully charged 30Q’s so it sounds like I have all the right materials to complete the test.

I almost just bought one. Understanding the concern and how to mitigate and test for it, from my perspective it’s off my list until the next version is out and gets tested. Haikelite needs to be deliberately careful after all the potential customers they lost already with other bungles, ignorance is not an excuse any longer.

Haikelite must put assembled light into a dark box to detect this faint light leakage. Their operator will miss it in a bright room.

I think the fake has big dot at the bottom left. Who has real Vishay SIR800 and care to share pictures?

These two Haikelite SIR800 giving me trouble right from start without extended use. Notice the dot is big. And I have to really adjust my phone camera angle in order to get clear picture on the printing.

Vishay SIR800 picture that I can find on internet. It has smaller dot printed.

And the Vishay SIRA60 I have bought has smaller dot too.

Here from an old mod:

And from a Manker U21 mod:

These were from ~2 years ago. I was buying the SIR800DP's from MtnE and maybe Mouser or Arrow at the time.

More:

The better 404:

Even better:

SIRA20DP spec sheet: https://www.vishay.com/docs/76212/sira20dp.pdf

SIRA60DP spec sheet: https://www.vishay.com/docs/66777/sira60dp.pdf

Maybe the A20 is slightly better, but some of the timing is a little slower.

Tom E, thanks for those pictures. There are a few differences compared to suspected fake SIR800.

1.The big dot on fake SIR800 is printed, I use a big magnifier and confirm that. While your pictures shows it should be engraved.
2.The big dot position on fake SIR800 is higher from the bottom edge.

In summary suspected fake SIR800 has cosmetic differences below:

The top picture is not showing up for me.

I happen to have some that I bought from MTN E a couple months ago. There is no printing on them, just laser etching.


.

Both of these differences may be normal production deviations and not the sign of one being imitation.

It could be the older 800's had the big dot because mine shown above date back quite a while. Even in the last 2 years, if I used them, it was to deplete old inventory. I haven't bought SIR800DP's in years because they were first obsoleted by the 404 then the A20, plus the Infineon.

Bought my first 800's in Jan 2016.

In summary suspected fake SIR800 has cosmetic differences below:


Jason, is this pic showing properly for you.
I mean to say laser printing of the big dot.

TomE, yours has big dot that’s part of the IC package, which is crafted on it, but mine are laser printed and at higher position.

Maybe we should send some pics to Vishay. I wonder will they respond.

Yes, I can see this picture. Is there supposed to be a difference between the left one and the right one? They look the same to me.

Some of Tom E’s pictures show the molded dot, but not all. His pic below shows a laser etched dot. I think the manufacturers vary how they label the chips. Vishay may also have more than one factory making the chips with slight differences in the labeling or one factory might do a molded dot and one a laser dot, etc… It is all quite complex.

There may not be a way to tell a real from a fake unless it’s through electrical measurements. You could have a real manufacturer crank out cheaply made, untested chips and put real, legit looking markings on them. Most will work properly so long as you don’t push it too close to it’s rated limits (the real chips rated limits). Some might have some “leakage” when off.

Here is your original picture of the leaky FET.

If I compare it to your picture of two chips I can see that the laser etched dot is quite a bit higher than the laser etched dot in Tom E’s picture. Is that the point you are trying to make?

I don’t know if that’s proof of a fake or just a slight difference in manufacturing.

I wonder if Vishay keeps a catalog of fake chips or pictures of fakes that they collect over the years? That would be interesting.

Those two identical FET are the suspicious SIR800 gave me trouble.
Yes, their position of big dot is not tally with real SIR800.

I think all SIR800 pics by Tom E have molded dot.

Molded dots don’t typically change color. Laser etched dots look more white because it burns into the surface. Same reason the lettering looks white. Who knows, it’s hard to tell by pictures.

They won’t most likely. I tried contacting a few manufactures about fakes in the past all to no avail. They either ignored me completely or gave me a run around and ended up saying I need to talk to the distributor I got it from, which was not possible of course. :person_facepalming:

Well, have you tried saying you’ve had fakes with the 5000pcs+ you’ve ordered?

I spent a few months trying to track down fake attiny85’s at one point, they were super slow to respond and after all that ended up getting no where and just saying to contact the distributor.

Some manufactures might be better to work with but the big ones just don’t seem to care for small orders like ours (small being anything sub ~100k units).

I’ve just sent an email to Vishay. Most likely they won’t reply me with helpful answer though.
On the webpage, Vishay acknowledge there are a lot counterfeits and advise their direct customer to buy from approved distributors only. But I think that doesn’t solve the problem of indirect customers buying a circuits having counterfeit Vishay components.