they don't seem fake, look at the attached picture.
Those are original ON Semi MC7812 and MC7912, same thin tab.
I've bought them from RS Components, a reputable world reseller.
Copper price is so much higher than in the past that ON reduced tab thickness, that's all.
Attachments
I can't imagine the LM3x7 being faked, real ones are cheap enough not to be interesting for conterfeiters, IMHO.
Don't let the thin tab of the LM337 in your pictures fool you, that's the single gauge case, and they probably are genuine. The style of the case and printing looks exactly like what I'm used to from ON Semi.
Other manufacturers, like ST and Fairchild, are also using single gauge cases (although recent ST LM317s seem to be dual gauge again). Also take a look at this post:http://www.diyaudio.com/forums/parts/82638-my-transistors-original-copy-29.html#post2349345.
The LM317 in your pics isn't one I recognize as typical ON Semi, but that doesn't neccessarily mean it's fake...
Last edited:
According to the marking diagram in the data sheet (page 10), the text is supposed to be right-adjusted. Yours is centred. I'm guessing fake.
Tom
Tom
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.