Hello, everyone.

Several years ago I de-soldered from an old VCR something that looked like a transistor, marked "I203 6F" (see picture). It used a TO-92S package, not hte ordinary TO-92. After testing it, I discovered it was an N-MOSFET. That was not much help because I still needed to know the absolute maximum ratings and such and so of the part.

The search for the datasheet was basically fruitless. I had an inkling it was from Toshiba because I had a few Toshiba transistors (C1740, I believe) that used the same package. Searching for "1203" (the "I" could be a sans-serif "1") showed a "2SK1203", which is indeed an N-MOSFET but in a TO-3P rather than a TO-92S package, and it is seemingly not from Toshiba.

Has anyone ever seen one of these?

Quote from: Mr.Oda on December 10, 2024, 10:45:13 AMSeveral years ago I de-soldered from an old VCR something that looked like a transistor, marked "I203 6F" (see picture). It used a TO-92S package, not hte ordinary TO-92. After testing it, I discovered it was an N-MOSFET. That was not much help because I still needed to know the absolute maximum ratings and such and so of the part.

At first I read it as 1203 V6F or 1203 W6F.  If it's not a Japanese part it could be VN1203 instead of 2SK1203, there are other suffixes.   I had a poke around but didn't get far though.   

Best bet would be to find a Service manual for the VCR.   The schematic will show a part number.

FYI, Japanese companies like Toshiba often use their own packages codes instead of TO-92S.  That makes it difficult to search if you are looking for TO-92S.  Here package, 2-4E1D,

https://www.alldatasheet.com/datasheet-pdf/pdf/30592/TOSHIBA/2SK192A.html

Maybe i203,

https://www.transistormosfet.com/en-gb/transistor?search=I203.

I also found a Sanyo SVC203, which is a vari-cap diode, but not sure if it's in the right package.
Seems so,
https://www.verical.com/datasheet/aptina-imaging-varactor-SVC203SPA-13806723.pdf

Quote from: Rob Strand on December 10, 2024, 12:09:59 PMAt first I read it as 1203 V6F or 1203 W6F.  If it's not a Japanese part it could be VN1203 instead of 2SK1203, there are other suffixes.   I had a poke around but didn't get far though.

Oops. The V (or W) is a scratch. I had to rub in some chalk to make the markings more visible to photograph. 

Quote from: Rob Strand on December 10, 2024, 12:09:59 PMBest bet would be to find a Service manual for the VCR.   The schematic will show a part number.

It never crossed my mind to consult the Service Manual. It is so simple that, well,  . Thank you very much.

Quote from: Rob Strand on December 10, 2024, 12:09:59 PMFYI, Japanese companies like Toshiba often use their own packages codes instead of TO-92S.

I should have guessed.

I'll see if I can find the VCR; it was saved, the metal case at least, for another project. Thanks for the help.

Quote from: Mr.Oda on December 10, 2024, 10:45:13 AM....not much help because I still needed to know the absolute maximum

It is not likely to be a 600 Volt KiloWatt part (maybe not even 1 Watt).

It is likely to be good for 12V and 100mA, which will cover a lot of small audio and switching jobs.

I may have seen a 3 Volt Max MOSFET but it was a very special fast part and $200 each, so would not be in a VCR.

The pinout may be the hard part. The Gate may be very easy to blow-out with static electric charge. It may take a lot of crossed wires(*) to tell S from D.

(*....or a smart tester... I'm too old to know)

Quote from: PRR on December 10, 2024, 07:38:26 PMIt is not likely to be a 600 Volt KiloWatt part (maybe not even 1 Watt).

It is likely to be good for 12V and 100mA, which will cover a lot of small audio and switching jobs.

30V to 60V range extremely likely.

Quote from: PRR on December 10, 2024, 07:38:26 PMThe pinout may be the hard part. The Gate may be very easy to blow-out with static electric charge. It may take a lot of crossed wires(*) to tell S from D.

(*....or a smart tester... I'm too old to know)

Curiously, that was the easy part: I used a smart tester.