Difference between 2N2222A and PN2222A #ubitx-help #ubitx40help


Jon Sumpter
 

Hi,
2N2222A are 6x more expensive than PN2222A. Is there some special reason the 2N2222A is specified to replace 2N3904s?
Please advise soonest.
Jon S


 

Hi Jon,

Looking at a few datasheets, I don't see any reason why you couldn't use them.  All the specifications are pretty much the same except for the thermal resistance of the package; and then the pn2222a was superior there even (I would have thought the opposite).

73,


Mark.


VE3MIC
 

Interesting

The differences are minimal, however the datasheets that I found indicate that the thermal properties are exactly the same for both, but show the max. collector current to be 1 amp for the PN2222A, and 0.6A for the 2N2222A.
de Mike


MVS Sarma
 

Perhaps Allison who suggested 2N2222 metal case ,did not mean against PN2222.

On Fri, Mar 15, 2019 at 6:04 AM VE3MIC via Groups.Io <ve3mic=yahoo.com@groups.io> wrote:
Interesting

The differences are minimal, however the datasheets that I found indicate that the thermal properties are exactly the same for both, but show the max. collector current to be 1 amp for the PN2222A, and 0.6A for the 2N2222A.
de Mike


 

Hi,

I tried to find sheets coming from the same manufacturer.  The ones from ON showed pretty similar max collector currents (probably they are not running up there anyway) and big differences on thermal resistance.

But what's really relevant here is to look at the Ft versus collector current graph and the hFE vs collector current graph where both look just the same.

73,


Mark.


 

Of course Allison may have real-world experience that show differences from datasheets...


VE3MIC
 

Getting even more interesting...

Your sheets show 0.8A for the 2N2222a and 0.6A for the PN2222a..
However your 2N2222a is in a TO-18 case, whereas, the spec sheets that I was looking at were both TO-92 case styles.

73 de Mike



Jon Sumpter
 

Thanks Mark, guna use em.


 

Hi Jon,

It's worth a try.  Searching back in posts, Allison did test the pn vs 2n and found the pn not as good, but it was still better than the 2n3904.  Probably it will depend on the quality and manufacturer of the pn part (although I think pn was specific to TI so it should be good quality, but there are lots of parts out there!)

If they don't work out let me know, I can try to find some 2n2222a or 2n5109 from my supplies to send you.

73,


Mark.


Lawrence Galea
 

I suggest getting a cheap 100 pack as found on the various sites and check them on one of the cheap multi testers and use those with the highest gain.
When using them in the push-pull stages use two with the same gain or as near as possible to balance them out.
no guarantees but at least you can try


On Sat, Mar 16, 2019 at 6:23 AM Mark - N7EKU <n7eku@...> wrote:
Hi Jon,

It's worth a try.  Searching back in posts, Allison did test the pn vs 2n and found the pn not as good, but it was still better than the 2n3904.  Probably it will depend on the quality and manufacturer of the pn part (although I think pn was specific to TI so it should be good quality, but there are lots of parts out there!)

If they don't work out let me know, I can try to find some 2n2222a or 2n5109 from my supplies to send you.

73,


Mark.


 

Not sure your budget,

But I saw 10 Motorola brand 2n2222a for $9.34 shipped on Amazon from a US seller.  Doesn't seem too bad?

73,


Mark.


ajparent1/KB1GMX <kb1gmx@...>
 

Perhaps Allison who suggested 2N2222 metal case ,did not mean against PN2222.
Sarma,

The metal can version has better thermal capabilities and higher peak current.

That and in every case where I've replace 2n2222A with PN2222 i never got the
same performance even at very low power (10mW) levels.  One is not the other in plastic.

FYI the 2n2219 is the same die as the 2n2222 in a TO5 can with improved thermal 
capabilities so its not onle better it shares the desirable characteristics to the higher
power level.

Generally I find that the PN2222 is a slight improvement over 2n3904 but not enough
to warrant stocking them in the lab here.

Allison


ajparent1/KB1GMX <kb1gmx@...>
 

Last time I purchased them it was 1.98$ ea for quantity more than 10.
I buy for project stock so rare is it than I buy one or two, last order it was 25!

We had a lot fo discussion last year and it comes down to this...   I know what
worked and wrote about it. also what was tried and a serious disappointment.

FYI testing for highest gain is not helpful as thats at DC, it is better if all the
devices had the SAME even if low gain.  Why?  You will not get more than
Ft/f at more than 10mhz.

So it comes down to do what you want and if it doesn't get the result, well, its your fault.
There is not such thing as a free lunch (TINSTAFL), in RF power that never more true.

Allison


Jon Sumpter
 

Allison,
Thank you for the heads up. The price was right so I'll try them. If I'm not happy with the output I'll do the cans.This is a learning process for me and as I told someone else: this is a train ride, a bit bumpy but the destination is great.
Jon S


barry halterman
 

Check out Dan's kits and parts.com for these 2N2222's in metal cans. He did have some JAN (military grade) available.


Lawrence Galea
 

Hi Barry, 
the link you posted takes you somewhere else

Dan's small parts link

Regards
Lawrence


On Tue, Mar 19, 2019 at 5:24 AM barry halterman <kthreebo@...> wrote:
Check out Dan's kits and parts.com for these 2N2222's in metal cans. He did have some JAN (military grade) available.


barry halterman
 

Thanks for clearing that up, Sir. I was half asleep when I posted that not realizing it became a link.


On Tue, Mar 19, 2019, 2:49 AM Lawrence Galea <9h1avlaw@...> wrote:
Hi Barry, 
the link you posted takes you somewhere else

Dan's small parts link

Regards
Lawrence

On Tue, Mar 19, 2019 at 5:24 AM barry halterman <kthreebo@...> wrote:
Check out Dan's kits and parts.com for these 2N2222's in metal cans. He did have some JAN (military grade) available.