hFE gain ranking of transistors & the letter suffix

[cvanc]

Is there a chart somewhere defining the hFE binning ranges?

Do these ranges stay constant across all transistors (i.e., if an "A" suffix on the p/n represents a beta of, say, 50-100 would it represent the same 50-100 range for any other transistor p/n?

Thanks.

[Benta]

No, the letters are relevant only inside one transistor type.
I'll give you an example: the well-known BC547 can be supplied as A, B and C, which divides the h_FE range in three.
The high-gain version, which it the BC549 will also come as A, B and C, but the actual h_FE values are different.

[cvanc]

No, the letters are relevant only inside one transistor type.

Wow, that certainly makes things more complicated.  Seems odd that this never got standardized?

I'll give you an example: the well-known BC547 can be supplied as A, B and C, which divides the h_FE range in three.
The high-gain version, which it the BC549 will also come as A, B and C, but the actual h_FE values are different.

OK, what happens if I buy the same transistors from a different manufacturer?  Would they agree as to the markings & the beta range they signify?  Or are all bets off if I dare to change brands?

Many thanks.

[T3sl4co1l]

BC847(A-C) I think is consistent.  2Nxxxx is divided into numbers, often by Vceo grade but there are some hFE graded parts as well.  Japanese numbers (2SCxxx, etc.) are whatever.  Also, there's Korea Electronics (KEC) parts marked similarly, but they are actually KTCxxx and such.

Tim

[David Hess]

No, the letters are relevant only inside one transistor type.

Wow, that certainly makes things more complicated.  Seems odd that this never got standardized?

Different transistor models have a different distribution of hfe.

I'll give you an example: the well-known BC547 can be supplied as A, B and C, which divides the h_FE range in three.
The high-gain version, which it the BC549 will also come as A, B and C, but the actual h_FE values are different.

OK, what happens if I buy the same transistors from a different manufacturer?  Would they agree as to the markings & the beta range they signify?  Or are all bets off if I dare to change brands?

If the part numbers are the same, then the beta ranges should be the same also although this is not part of the JEDEC registration.

Older parts like the 2N5088/2N5089 tend to use different part numbers for different hfe ranges or colored dot markings like the 2N2926.

[rsjsouza]

OK, what happens if I buy the same transistors from a different manufacturer?  Would they agree as to the markings & the beta range they signify?  Or are all bets off if I dare to change brands?

Many thanks.

Always resort to the manufacturer's datasheet.

For example, some of the best transistor datasheets were from Philips (I had a few of their books in the 80's), but over the years they removed most of the curve characteristics on several of their modern revisions.
Old Philips:
http://grabstore.ehv.campus.philips.com/voorraadmap/hfdst01_transistors/Datasheets_pdf_files/bc550.pdf

Newer revision:
https://media.digikey.com/pdf/Data%20Sheets/NXP%20PDFs/BC549,550.pdf