Counterfeit 2SC2240

[tarior]

I was working on a customer's Marantz 140 today, and I wanted to replace the differntial input pair with some 2SC2240 transistors. I got to looking at what I had, and they were very different from each other.
The one on the right is a genuine Toshiba part from Mouser. The one on the left is an apparent fake, I'm not sure where it came from. It's pretty sad when the Chinese are counterfeiting 20 cent transistors.

[Stuart Pedaso]

Care to crack a couple open to compare dies?

[tarior]

The dies appear to be similar sized, the pinout is NOT correct. It really pains me to wreck a perfectly good transistor, BTW.

Again, Toshiba part on the right, fake on the left. It's hard to tell without a magnifier, but the Toshiba is better quality. Note the discoloration about the die on the fake part.

[glen65]

Originally Posted by tarior

The dies appear to be similar sized, the pinout is NOT correct. It really pains me to wreck a perfectly good transistor, BTW.

Again, Toshiba part on the right, fake on the left. It's hard to tell without a magnifier, but the Toshiba is better quality. Note the discoloration about the die on the fake part.

It appears that one is also a different pin out.

[avionic]

Originally Posted by avionic

Did the "so called" fake..work in the circuit. There is more than just Toshiba legitamately making these.And yes they can have different pin-outs.

http://www.datasheetarchive.com/data...A00422945.html

[QUOTE]Datasheet Home \ Datasheet Details
--------------------------------------------------------------------------------




ST 2SC2240
TO-92 Plastic Package Weight approx. 0.19g
ST 2SC2240
NPN Silicon Epitaxial Planar Transistor for low noise audio amplifier applications. The transistor is subdivided into two groups, G and L according to its DC current gain On special request, these transistors can be manufactured in different pin configurations.
TO-92 Plastic Package Weight approx. 0.19g
G S P FORM A IS AVAILABLE
SEMTECH ELECTRONICS LTD.
(Subsidiary of Semtech International Holdings Limited, a company listed on the Hong Kong Stock Exchange, Stock Code: 724)
Dated : 07 / 12 / 2002
ST 2SC2240
G S P FORM A IS AVAILABLE
SEMTECH ELECTRONICS LTD.
(Subsidiary of Semtech International Holdings Limited, a company listed on the Hong Kong Stock Exchange, Stock

[ecluser]

Originally Posted by avionic

Did the "so called" fake..work in the circuit. There is more than just Toshiba legitamately making these.And yes they can have different pin-outs.

http://www.datasheetarchive.com/data...A00422945.html

When we want a 2SC2240, we don't just want a transistor that work in a circuit, we want a low noise transistor.

Yes, the Chinese are counterfeiting 20 cent transistors.


I can send you a 2SC2240 that will not work. I bought six 2SC2240 from a local parts store (by chance they had only 6 in their stock!) and when I tried to match them, I couldn't measure their hFE, no matter what pin-out I tried.

I put them on my beloved curve tracer and it turns out that all of them were very bad PNPs !!!

Since this misadventure, I never buy transistors from this store (ÉlectroMike in Québec city).

In the picture on the first post, we can see that the left one is labeled c2240 Y. As I know, the hFE classification for the 2SC2240 is GR or BL. I didn't check all the datasheets for the 2SC2240 to see if some manufacturers use the Y classification...

[avionic]

I get all my japanese tranny's at BDent haven't had a lick of problems. But I usuaully match up the suffix codes as well BL,GR. etc. BD has a very large selection. They also have a $15 min. order so I usually end up buying extra quantities..
http://www.bdent.com/

[glen65]

Originally Posted by ecluser

When we want a 2SC2240, we don't just want a transistor that work in a circuit, we want a low noise transistor.

Yes, the Chinese are counterfeiting 20 cent transistors.


I can send you a 2SC2240 that will not work. I bought six 2SC2240 from a local parts store (by chance they had only 6 in their stock!) and when I tried to match them, I couldn't measure their hFE, no matter what pin-out I tried.

I put them on my beloved curve tracer and it turns out that all of them were very bad PNPs !!!

Since this misadventure, I never buy transistors from this store (ÉlectroMike in Québec city).

In the picture on the first post, we can see that the left one is labeled c2240 Y. As I know, the hFE classification for the 2SC2240 is GR or BL. I didn't check all the datasheets for the 2SC2240 to see if some manufacturers use the Y classification...

PNP?
Wow..I guess they did screw them up.
Don't know if you would be interested but Fairchild make
a direct low noise replacement for these, KSC1845.
http://www.fairchildsemi.com/ds/KS/KSC1845.pdf
You could probably get some samples and give them a shot.

Originally Posted by avionic

I get all my japanese tranny's at BDent haven't had a lick of problems.
http://www.bdent.com/

So far Ive had no problems with them myself.

[avionic]

Originally Posted by ecluser

When we want a 2SC2240, we don't just want a transistor that work in a circuit, we want a low noise transistor.

Yes, the Chinese are counterfeiting 20 cent transistors.


I can send you a 2SC2240 that will not work. I bought six 2SC2240 from a local parts store (by chance they had only 6 in their stock!) and when I tried to match them, I couldn't measure their hFE, no matter what pin-out I tried.

I put them on my beloved curve tracer and it turns out that all of them were very bad PNPs !!!

Since this misadventure, I never buy transistors from this store (ÉlectroMike in Québec city).

In the picture on the first post, we can see that the left one is labeled c2240 Y. As I know, the hFE classification for the 2SC2240 is GR or BL. I didn't check all the datasheets for the 2SC2240 to see if some manufacturers use the Y classification...

I only see GR and BL...

[tarior]

Like ecluser said, I want the 2240 that Toshiba shows a datasheet for. If the pinout is different than Toshiba's datasheet, it's phony part as far as I'm concerned. Furthermore, what are the chances that these things are going to meet the proper noise, current, voltage and cutoff specs? I'm betting slim to none. They aren't identical or interchangeable, and I'm sure as heck not gonna stake my reputation on them.

As an example on the same topic, I keep Toshiba 2SC2383 on hand for a good all around replacement NPN. I've also bought Fairchild KSC2383, and you know what? Their spec sheet is practically identical to Toshiba's. Pinout, current, voltage, everything. In this case, these are basically the same transistor from two different mfrs.

A tech can do a hundred perfect jobs in row, but the one people will talk about is the one that turned to shit because of bad parts.

[tarior]

I actually ended up using KSC1845 in this case, but it only has half the current capacity of 2SC2240. I'm ordering new Toshiba 2SC2240s from Mouser in the morning.

[dr*audio]

I bought my 2SC2240's from MCM Electronics, and they have BL on them. The HFE measures around 380.

[avionic]

When we want a 2SC2240, we don't just want a transistor that work in a circuit, we want a low noise transistor.

A noisy transistor I would not consider working... I was just stating that there are other companys legit or not unloading these on the market.And obviously there is junk out there.

[tarior]

Originally Posted by dr*audio

I bought my 2SC2240's from MCM Electronics, and they have BL on them. The HFE measures around 380.

Most likely the real deal, and you can tell by the lettering.

[tarior]

Originally Posted by avionic

A noisy transistor I would not consider working... I was just stating that there are other companys legit or not unloading these on the market.And obviously there is junk out there.

With all due respect to you, in this case if it's not Toshiba, it's a junk fake as far as I'm concerned.