ordering transistors from Mouser - different types? confused

[kato]

I've got a stompbox schematic that calls for these transistors:

2n5087 and
2n5088

A search on Mouser.com gives
2n5087 for 26¢
or 2n5087TA for 6¢

Is it OK to save the twenty cents and get the "TA."
Does TA stand for something insidious?
Am I just being a cheap ass?

Inquiring minds want to know.

 

[alk509]

Datasheets, datasheets, datasheets...

Peace,
Al.

 

[PRR]

> A search on Mouser.com gives 2n5087 for 26¢ or 2n5087TA for 6¢

The $0.26 price is high. These are nickle-dime parts. Central doesn't make transistors, they must be re-marketers.

> Datasheets, datasheets, datasheets...

They all link to the same datasheet, which does not explain the suffixes.

http://www.fairchildsemi.com/pf/2N/2N5087.html does list all the suffixes, confirms that the TA is a TO92 part (we might not want the weeny surface-mount version), and implies that the differences are in the packaging (bulk or taped) and they are all 4 cents/each in thousands.

And my impression is that all 2N5087s are electrically the same. The difference is the package. Some are surface mount, bad for casual DIY. Some are now lead-free to meet strict laws. The factory packs them in lots of 1,000 and 10,000, and a high-production assembly line may need specific packaging to feed into their stuffing machinery. In DIY, you just want to be sure to get the TO92, not surface-mount.

I think Mouser has bought different variants under different contracts and marked-up the Per-Each price in different ways. So through a fluke of their purchasing and pricing history, today the TA version happens to be low-boy on the price list.

TA packaging is "Ammo" which is on-tape in a box. "Reel" is on-tape on a reel. You don't care which if you are buying less than a box/reel-full: what you will get is a few inches of incredibly sticky tape with TO92s in it. The "BU" variant is "bulk" which may be un-taped, and may be less annoying; but Mouser won't sell you less than 10,000 (probably a whole box full of loose TO92s). I suppose they have a tape dispenser that will chop-off 1 or 10 or 100 units of tape, and don't want to mess with open boxes of loose TO92s.

Get the 6-cent version.

It is remotely possible the $0.26 version is not-taped; that Central is charging $0.20 each for dispensing from 10K boxes or splitting tape, possibly bagging each part for easy counting. And it is even possible I would pay $0.20 to NOT deal with tape. But they don't speficially say "loose" or "bagged", so it might just be a greed-price.

 

[pmroz]

i've ordered Mouser only a couple times, TA means tape over there, as PRR said. I think TAR means cut tape/reel, not sure how that's different. For BC550C/ 560C transistors, which needed matching, i liked the tape. It's easy to go down the line, and write the values right on the tape. Same with resistors. When not on tape, the Rs roll around while you're poking leads or clips at them. Then you have to make a sticker with value for each. Very slow, and the little sticker tags can fall off.
So my opinion, tape saves mucho time while matching. If you're not matching or don't need true values of your components, doesn't matter except for price and glue residue.

BTW ordered 100 'BC550CTA' (.04) and 2 'BC550C' (.26? or so), they were exactly the same part.

 

[kato]

Wow guys, thanks for all the useful info. Very helpful.

The "TA" versions are listed as TO-92 which is the only reason I even considered them. They both said, "NPN" both "TO-92" and were not surface mount so I added them to my cart.

But I didn't want to place my order till I heard your advice. Thanks!

I always like to order a few extra for inexpensive parts like this in case of future projects. So at this price, I can order a few extra of each and still be under 26¢!

I don't mind the tape residue. I'm already in the habit of removing it from each component before soldering anyway!

Thanks guys,

Kato

 

[PRR]

> TA means tape over there.... I think TAR means cut tape/reel, not sure how that's different.

Read http://www.fairchildsemi.com/products/discrete/pdf/to92_tr.pdf

This does explain the T, A, B, and some other options.

Mostly, mass-producers want tape so they don't have to fondle each part onto the board. "Ammo" is tape folded up in a box like ammunition for a WWII machine gun. "Reel" is a big cardboard film-reel. Now when you ask for "reel", you have to specify if the parts face left or right, up or down (A, B, C, D).

None of this matters a bit if you buy less than a full reel/box, or if you are not belt-feeding automatic stuffing machinery. Oh, I suppose a snip from a reel is curved and a snip from a box has a kink every 6 inches, but all the same to you.

Another thing to note: Fairchild (and I think codes like these are semi-universal) will bend or trim the leads in different ways for you. Original TO92, ProElectron 94, fit TO-18, fit TO-5, spread to fit 0.002" holes, emitter lead cut short, all leads cut short.