Why would the datasheet have specifics of the technology used? It could well be regarded a trade secret. The data in the datasheet speaks for itself.
There are fake J162/K1058 around but they are not that common since Renesas (ex. Hitachi Semiconductor) manufactures them currently and the prices are not exorbitant. The fakes generally have the drain on the middle pin, originals have the source. The source being on the body of the silicon die is a byproduct of lateral design, it is also difficult to fake because doing so requires the fakers to make a custom package frame, which makes the fake more expensive than the original. The other characteristic which can be checked is the very low treshold voltage, easy to measure with a DVM that has a diode test setting.
What is possible are rejected parts that were 'recycled' from a factory that originally makes them, there have been many reports about this, specifically with parts from China and India. Also, recycled and prototype parts re-labelled - but this is more common for chips than discretes.
There are fake J162/K1058 around but they are not that common since Renesas (ex. Hitachi Semiconductor) manufactures them currently and the prices are not exorbitant. The fakes generally have the drain on the middle pin, originals have the source. The source being on the body of the silicon die is a byproduct of lateral design, it is also difficult to fake because doing so requires the fakers to make a custom package frame, which makes the fake more expensive than the original. The other characteristic which can be checked is the very low treshold voltage, easy to measure with a DVM that has a diode test setting.
What is possible are rejected parts that were 'recycled' from a factory that originally makes them, there have been many reports about this, specifically with parts from China and India. Also, recycled and prototype parts re-labelled - but this is more common for chips than discretes.
Usually fake transistors can be seen from its horrible build quality. Well, like almost any other fake stuffs.
I cannot say whether the picture from your link is fake or not but all my transistors I have ever used obviously have far more superior build than that.
Fake transistor usually have poor marking, shinny metallic, and the corner is not really perpendicular (looks like the metal was cut using poor technology/cutter).
But the easiest way to know whether it is fake or not is by listening to it
(especially for plastic stuff like LM3875TF)
Lateral MOSFETs from Exicon and Renesas are oriented GSD -- whereas the IRF devices are GDS.
Easiest way to tell if they're fake is to measure the threshold voltage -- see the PASSDIY website for easy ways of doing this -- a lateral will have a threshold voltage well below 2 volts, transconductance at 1 amp of about 1S.
Easiest way to tell if they're fake is to measure the threshold voltage -- see the PASSDIY website for easy ways of doing this -- a lateral will have a threshold voltage well below 2 volts, transconductance at 1 amp of about 1S.
My IRF540/9540 are shiny like polished and silvery on the back while the edges look like copper cut with a shear, do this mean their fakes ?
I also have IRF3205's but those are dull and have a kinda texture on the back and no visible copper on the edges, but i see that alot on older transistors.
I also have IRF3205's but those are dull and have a kinda texture on the back and no visible copper on the edges, but i see that alot on older transistors.
Not all devices are ever manufactured with high quality build, but most are. You'll know this if you have worked with many of them before.
For me, the lower quality build (of the same manufacturer) is not necessarily a fake, but a lower quality one. For example, why manufacturers manufacture lower quality parts to be sold (and produced) in the third-world countries? Economy of course.
It is common to find a "fake" transistors in Asia, from something not obviously fake, to something obviously fake. Like many other products from China we know about "KW-1" products, "KW-2" or "KW-3". The most obvious fake transistors are the most commonly used transistors like 2N3055/2955. You can find them in most electronic shops here. They are almost always cheaper than usual. So KW-3 is cheaper than KW-2 and KW-2 is cheaper than KW-1. This, no doubt will help those who can't afford to buy expensive parts?
TO-220 IRF (like IRF540/9540) are industrial standard and widely used for switching purposes. It is easy to source them in electronic shops. So yes, I have found various different build quality of this product, and I will avoid them especially when "ON" is printed on them (imo, Onsemi/Motorolla parts must have high quality build than IR/International Rectifier). These are high current devices (voltage SOA also wide) to be used in power supply so even if it is fake it should not fail in amplifier applications. And it's quality for audio mostly determined by its capacitance (which is commonly high) so I don't think it is something to worry about.
Hello
All I can write I purchased on Ebay Sanken transistors , I the first power up they exploded .
I never sow something like than in the last 21years DIY .After I checked all parts and everything was in the right place how should.
Also I sow many counterfeit Toshiba deice 2SC5200 ,an Hitachi lateral mosfet .
The best think to avoid Ebay when you search for semiconductor an try to buy companies like Mouser, Digi Key , Ark electronics , Etc.
It is not wort to save a back or two and get garbage for your money.
Greetings
All I can write I purchased on Ebay Sanken transistors , I the first power up they exploded .
I never sow something like than in the last 21years DIY .After I checked all parts and everything was in the right place how should.
Also I sow many counterfeit Toshiba deice 2SC5200 ,an Hitachi lateral mosfet .
The best think to avoid Ebay when you search for semiconductor an try to buy companies like Mouser, Digi Key , Ark electronics , Etc.
It is not wort to save a back or two and get garbage for your money.
Greetings
This thread should be locked. No need to further discuss, or prove anything, or provide any evidence. If anyone wants evidence, I will provide it at your own expense. Please purchase a 2SK1058 MOSFET from Hong Kong on eBay, then purchase another one from an official Hitachi distributor. Send them both to me. I will cut them both open and post pictures for everyone to see. All electronic parts from China/Hong Kong (especially from eBay) are fake. All 100% of them. To those who buy from eBay, YOU and only YOU are the problem for this epidemic. And all because you want to save 50 cents here and 25 cents there. If you can't afford it, don't build it.
1) That's not correct.
2) Tell me of a US Distributor with 2SJ162 in stock at the moment.
Eek, if needed i can get them within 10 minutes.
(just the +$9 single item figure that bothers me)
All electronic components from china cannot be fake at all!! All components nowdays are MADE IN CHINA!!! USA havent produced transistors for years, all they do now is this fpga/computer cpu stuff.
Those why say everything from ebay is fake have just had a bad experience with ebay, such as getting the wrong part or not gotten anything at all.
Or they are ppl that work for mouser, digikey, farnell and others just trying to win more customers by telling false stories about every component from china is fake.
There are fakes floating around but its nowhere near as common as some ppl here claim, i've bought transistrors and ic's from ebay for the part 10 years and not one of them have proven to be a fake. All my failures have been user errors like miswiring, overcurrent or overvoltage.
My mosfet amp wouldent be working at all if the transistors used were fakes.
Those why say everything from ebay is fake have just had a bad experience with ebay, such as getting the wrong part or not gotten anything at all.
Or they are ppl that work for mouser, digikey, farnell and others just trying to win more customers by telling false stories about every component from china is fake.
There are fakes floating around but its nowhere near as common as some ppl here claim, i've bought transistrors and ic's from ebay for the part 10 years and not one of them have proven to be a fake. All my failures have been user errors like miswiring, overcurrent or overvoltage.
My mosfet amp wouldent be working at all if the transistors used were fakes.
Hehehe that seems to be a strange thing to most of you. But not for me. In my neighborhood, there is no secret here. Everybody know that there are at least 4 classes of the Sanken. The cheapest is around 3.9$. The most expensive is around 8.9$. They say that the 8.9$ one is the original but I don't think so.
The cheapest one is usually recommended by the seller for only 30-35V of power supply. The higher the Vce threshold the more expensive it is, and the more power of course. So, what happen if you purchase one of these cheap Sanken and think that the maximum Vce is 180V? Hehehe
In my area, it is very very very hard to find original popular parts such as Sanken 2922 and 3055. What you need to do is just to calculate how big the probability for the fake transistors to go to ebay.
Selling original Sanken in my area might not be profitable (and producing the fake ones surely is) so what is so strange about this?
If you want to have original Sanken, go to ESP site and check the different in characteristics between the original and the fake one. The fake ones do not have the rounded edge feature yet, but may be soon. The shiny metal is so common with fake ones, may be because they are cheap result of metal recycling process.
Fake transistors, even if they can withstand specified voltage/current, do not sound the same. Poor you guys (if you think you have a hi-end amp)
Regarding Electronics Salon, according to these pictures, those transistors seem genuine to me. We should be careful when accusing somebody only because he's selling transistors over ebay. Buy the transistor, test them, build an amplifier or smash them open and then make a conclusion. Besides, would you give your left hand for Digikey or Farnell to prove they are selling genuine parts!?
Edit: http://www.diyaudio.com/forums/solid-state/167550-sanken-2sa1216-2sc2922-genuine-fake-pictures.html
Edit: http://www.diyaudio.com/forums/solid-state/167550-sanken-2sa1216-2sc2922-genuine-fake-pictures.html
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> All electronic components from china cannot be fake at all!! All components nowdays are MADE IN CHINA!!!
Absolutely correct.
Discrete semiconductors do not make money. Price is too low.
Only place to make these would be China, Philippines, Mexico, Vietnam, ....
If they are made in the States (perhaps SemiSouth), then they are unaffordable.
Linear Systems, e.g. is a fabless company. Their JFETs come from foundries.
The same goes for Loveltech. No one complained they sound terrible.
> USA havent produced transistors for years, all they do now is this fpga/computer cpu stuff.
Have a search and see how many fabs Intel has in the US, and how many overseas.
And >>80% of the memory chips are made in Asia (Korea, Taiwan, Japan, ....).
So are 90% of the rare earth magnets, including those from Vakuumschmelze.
Patrick
Absolutely correct.
Discrete semiconductors do not make money. Price is too low.
Only place to make these would be China, Philippines, Mexico, Vietnam, ....
If they are made in the States (perhaps SemiSouth), then they are unaffordable.
Linear Systems, e.g. is a fabless company. Their JFETs come from foundries.
The same goes for Loveltech. No one complained they sound terrible.
> USA havent produced transistors for years, all they do now is this fpga/computer cpu stuff.
Have a search and see how many fabs Intel has in the US, and how many overseas.
And >>80% of the memory chips are made in Asia (Korea, Taiwan, Japan, ....).
So are 90% of the rare earth magnets, including those from Vakuumschmelze.
Patrick
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