General > General Technical Chat
How Do Chinese Suppliers Have So Much Better Prices, Even On American Products?
<< < (4/6) > >>
dietert1:
Yesterday i opened a 2N3055 marked TRANSUN (chinese origin), that failed in a linear power supply after some weeks taking about 40 W at 30 °C case temperature. During repair that transistor first seemed OK except i noticed a somewhat higher Ube. Then while testing the repair the transistor failed with the emitter interrupted. Yesterday i opened it and found a good chip inside soldered to a steel base plate, with two loose bond wires for the emitter. The base bond wire came off when i tried to blow away the sawdust from inside the transistor.

They knew they had a problem with bonding. There were two emitter wires instead of one and some white rubber-like glue on top of the chip meant to hold all bond wires in place. We have another of those supplies with two similar TRANSUN 2N3055 and their Ube exhibits a 0.1 V difference. Probably one of them already lost one of its emitter bond wires, too. And when the second bond wire goes, so will the other 2N3055 in that supply.

Just an example. Sometimes the decision for the lowest price isn't exactly wise.

Regards, Dieter
SilverSolder:

--- Quote from: blueskull on December 18, 2020, 02:20:24 pm ---Simple. We order in bulk. [...]

--- End quote ---

My grandmother taught me that when I was a kid.   As a 7 year old, I was in awe at her 25Kg sack of sugar to do her fruit preserves in the fall - I had never seen so much sugar in one place.  She said, "poor people buy sugar one tiny bag at a time, and pay three times as much for it.  That's why they are poor, they never do the smart thing."
BravoV:

--- Quote from: SilverSolder on December 19, 2020, 03:33:19 pm ---
--- Quote from: blueskull on December 18, 2020, 02:20:24 pm ---Simple. We order in bulk. [...]

--- End quote ---

My grandmother taught me that when I was a kid.   As a 7 year old, I was in awe at her 25Kg sack of sugar to do her fruit preserves in the fall - I had never seen so much sugar in one place.  She said, "poor people buy sugar one tiny bag at a time, and pay three times as much for it.  That's why they are poor, they never do the smart thing."

--- End quote ---

The words ... size does matter come into play here.

If you're bored, just skip to year 2012 when China toppled the top one, abit flip flopped, but once 2017, it just went on booster mode.




... or just technology exports which covers aerospace, computers, pharmaceuticals, scientific instruments, and electrical machinery, China moved to the top at 2004.



Trader:

--- Quote from: blueskull on December 19, 2020, 03:04:44 am ---since Toshiba has stopped producing them decades ago
--- End quote ---

Toshiba still producing and selling those FETs.

https://toshiba.semicon-storage.com/ap-en/semiconductor/product/bipolar-transistors-igbt/detail.2SA1943.html

https://toshiba.semicon-storage.com/ap-en/semiconductor/product/bipolar-transistors-igbt/detail.2SC5200.html


--- Quote from: blueskull on December 19, 2020, 03:04:44 am ---Chinese branded, parameter (or at least paper parameter) equivalent to be fake or not fake
--- End quote ---

If you cannot comply with all the Specs, you cannot use the same part name, this is called "Counterfeit".

And the chinese NEVER release a "New" datasheet, they sell the FAKE component with the same Name and Specs as the Original one.
SilverSolder:

--- Quote from: Trader on December 19, 2020, 04:57:37 pm ---[...] If you cannot comply with all the Specs, you cannot use the same part name, this is called "Counterfeit". [...]

--- End quote ---

But even the brand owners are not living up to all the specs, when they move a product from an old process to a new one.  The new product is therefore an imperfect copy...  it may be "good enough for Australia" in most ways, but it isn't necessarily going to perform like the old model.

Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod