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Design >> Analog Design >> What and why is 2N3904 BJT transistor?
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Message started by neoflash on Jun 6^th, 2020, 10:44am

Title: What and why is 2N3904 BJT transistor?
Post by neoflash on Jun 6^th, 2020, 10:44am

I googled and it is a typical transistor BJT. But what do the number and symbol stands for?

Thanks!

Title: Re: What and why is 2N3904 BJT transistor?
Post by Ken Kundert on Jun 6^th, 2020, 12:32pm

It is a JEDEC number. JEDEC is a standards body for the US. Europe and Japan both have their own naming schemes.

2n signifies a transistor. 3904 is just assigned sequentially. 2N3904 happens to be a fairly popular transistor. 2N2222 is the JEDEC number of another very popular transistor.

See JEDEC Numbering.

-Ken

Title: Re: What and why is 2N3904 BJT transistor?
Post by neoflash on Jun 6^th, 2020, 4:47pm

Ken Kundert wrote on Jun 6^th, 2020, 12:32pm:

Great knowledge Ken. MMBT3904 what does MMBT stand for?

Title: Re: What and why is 2N3904 BJT transistor?
Post by Andrew Beckett on Jun 7^th, 2020, 1:00am

I believe this is just a prefix used by a different manufacturer. MMBT is (I think) used by On Semi (probably coming from one of their many acquisitions over the years). Other prefixes used are discussed in this post

So I think it's another manufacturer's implementation of a common generic device.

Andrew.