J111/J112/J113 pinout confusion

[Fancy Lime]

Hi there,

I had some trouble getting J113 switches to work and after some debugging I went back to check it I may have remembered the pinout wrong. So I looked it up only to find two different pinouts for the TO-92 package in datasheet from OnSemi. The 1997 datasheet, still published under the name Fairchild, says DSG, whereas the 2020 datasheet, which does not mention Fairchild anymore, says GSD. Sure enough, I thought the ones I used were the latter but really were the former. I'll have to check the others I have and see what's what. But really the question is: WTF? Anyone else had that problem?

Cheers,
Andy

[pacealot]

I thought it was just me being an idiot (I mean, I was and am, but it's possibly a separate issue in this instance), but I recently fried about three J111s just trying to test them for Vp/Idss because I was evidently working off the wrong datasheet myself. I didn't keep track of which datasheet was correct and which one wasn't, but I seem to recall that the J111s turned out to be GSD in reality (which matches almost all my other JFETs, which is the only reason I remember). I had got them from Mouser last summer, I think.

I'm glad to know that I'm not the only one!

(But I still blame myself for not keeping notes after frying the first one to prevent myself from doing it again...)

[duck_arse]

OnSemi datasheet marked
"Publication Order Number: J111/D March, 2006 − Rev. 2"

shows TO−92  CASE 29−11  STYLE 5, which is what we'd expect for a J series fet,

whereas
"Publication Order Number: MMBFJ113/D September, 2020 − Rev. 3"

shows TO−92 3 4.825x4.76  CASE 135AN [and case 135AR]

and it seems that hanging "3" covers the confusion, as it's pins the other way round. you would have to hope that suppliers were across this.

[Rob Strand]

I'm very skeptical of the correctness of modern datasheets, for old or new parts.   

My paper copy of the 1983 Motorola databook shows,

  \ d  s  g/  when viewed from the bottom.

It's a TO-92 package, Case 29 Style 5.  Style 5 is pin 1 drain, pin 2 source, pin 3 gate;  \ 1 2 3/ as viewed from the bottom.

I have noticed the disagreement in the J111/J112/J113 pinouts on the various pdf datasheets.

FWIW, Motorola became On-semi long before Fairchild was taken over.

[Mark Hammer]

This is why I keep saying, only half tongue in cheek, that you'd think there wouldn't be quite so many pinouts for FETs and bipolars with only 3 pins....but you'd be wrong.  I find the best thing to do is to do an image search for the specific transistor, in order to see if there is a 3D drawing.  I can never tell if the other drawings are looking down on the transistor or up.

[Rob Strand]

The National Semiconductor JFET Databook 1977 (scanned), shows

\  d s g /   bottom view

with numbering,

\ 3 2 1 / bottom view     ;   1 = g, 2 = s, 3 = d

So they managed to match pinouts despite the pin numbering differences.

[iainpunk]

I'll have to check the others I have and see what's what. But really the question is: WTF? Anyone else had that problem?

check all jfets when you get them, especially off of ebay, they can be both directions in one batch, i always check with DMM and mark the gate with some blue paint pen.

cheers

[jonny.reckless]

To add to the fun, the drain and source are interchangeable on J11x 

The latest ON semi datasheet has the correct pinout shown: https://www.onsemi.com/pdf/datasheet/j111-d.pdf

Don't trust pin numbering on TO-92 packages, just look carefully at the datasheet. Every J112 I've ever seen in 30+ years has the same pinout.

[Fancy Lime]

So I measured and mine are all DSG, like most datasheet say. BTW, here is the one that claims GSD:
https://www.onsemi.com/pdf/datasheet/mmbfj113-d.pdf
So the big question is, did they actually change the pinout last year (I would not put it past 2020 to pull that kind of stunt) or is it just an error in the datasheet?

Andy

[duck_arse]

TO-92-3. it's there in the datasheet. it's there in mouser/digikey part/data/blubs. wether or not they are paying enough attention, or the end user notices the different part number, different matters.

[Fancy Lime]

TO-92-3. it's there in the datasheet. it's there in mouser/digikey part/data/blubs. wether or not they are paying enough attention, or the end user notices the different part number, different matters.

Well, I certainly did not pay enough attention. Now that you mentioned it (also in your earlier post, which I somehow skipped, I need more sleep, apparently), I see the "3". Very unassuming and hidden. Not a great way of naming things but hey, definitely my mistake for not knowing the intricacies of the pinout naming scheme. I'm guessing this has lead to some costly manufacturing errors. Glad I learned to watch out for that in the future.

Cheers and thanks for the help,
Andy

[Rob Strand]

Well, I certainly did not pay enough attention. Now that you mentioned it (also in your earlier post, which I somehow skipped, I need more sleep, apparently), I see the "3". Very unassuming and hidden. Not a great way of naming things but hey, definitely my mistake for not knowing the intricacies of the pinout naming scheme. I'm guessing this has lead to some costly manufacturing errors. Glad I learned to watch out for that in the future.

I can see how mouse/digikey can separate the parts with their own part numbering.   In fact their own part number can separate manufacturer alone regardless of whether the part specs are different or not.

When looking at parts via the manufacturer's web site,  the OnSemi website comes up as a plain J111/J112/J113 without any specific suffixes to identify the part as being different.    Motorola changed to OnSemi long ago so they have been making the common pinout version for yonks.   For them to change the pinout without adding a suffix is outright dodgy.

Different pinouts for the same device was handled in the past by Mototola/OnSemi, for example 2N2222/2N2222A vs MPS2222/MPS2222A.


EDIT:
Here you go Onsemi Rev 2, 2006/2007, common pinout,  (notice no J113)

https://www.onsemi.com/pdf/datasheet/j111-d.pdf

Notice the filename for the dodgy pinout version is mmbfj113-d.pdf
https://www.onsemi.com/pdf/datasheet/mmbfj113-d.pdf

The J111/J112 vs J113 thing is suspicious.

But earlier, Rev 1 2001, has all three with the common pinout,
https://www.scribd.com/document/102961595/j111-Jfet-Channel-n-3
https://www.uk-electronic.de/PDF/J112.pdf

[Rob Strand]

FYI, this datasheet has been updated in March 2023.
It contains info on the common variants of the J11x JFETs.

https://www.onsemi.com/pdf/datasheet/mmbfj113-d.pdf

The file with the dodgy pinout mentioned in the previous post has be replaced (by ON).
The same link finds the new version of the file.

However, be warned.  You only find this datasheet when you look for J113.
If you look for J111 or J112, you will get links to the older datasheet (March 2006, which doesn't have the J113).

[Strategy]

Just 5 minutes before seeing this thread I was ordering J111 and J113 on Digi-key to repair a busted DOD FX60 chorus that came to me a while back.
Really glad to have seen and stopped to read this - I'd never have expected to discover potentially different pinouts 

[Rob Strand]

Just 5 minutes before seeing this thread I was ordering J111 and J113 on Digi-key to repair a busted DOD FX60 chorus that came to me a while back.
Really glad to have seen and stopped to read this - I'd never have expected to discover potentially different pinouts 

At the end of the day, no real problem but a lot of confusion caused by errors in the previous version of the mmbfj113-d.pdf datasheet.

While the thread was running you have to give the datasheet the benefit of the doubt and suspect the manufacturer changed something.   By the end of the thread I was fairly convinced the datasheet had a bug.   Anyway, it's all fixed by ON's update.

[PRR]

Thanks for new datasheet.

J113, fig 7, says "rDS, DRAIN "ON" RESISTANCE (mΩ)", 10 to 100. This more likely NOT "m" milli?
https://www.onsemi.com/pdf/datasheet/mmbfj113-d.pdf

Fig 9 and 10 also have Ω but is likely 1/Ω Mhos? (now siemens)

[Rob Strand]

Thanks for new datasheet.

J113, fig 7, says "rDS, DRAIN "ON" RESISTANCE (mΩ)", 10 to 100. This more likely NOT "m" milli?
https://www.onsemi.com/pdf/datasheet/mmbfj113-d.pdf

Fig 9 and 10 also have Ω but is likely 1/Ω Mhos? (now siemens)

Yep, more mistakes.  Changing stuff that shouldn't be touched!

Vgs = 0 got changed to Vgs(off) = 0; which doesn't make sense.

Someone has decided mho is ohm and then changed it to the ohm symbol.

Fairchild 2012 has the correct plots and units:




PS: sorry I accidentally edited your post.  I restored it but I somehow left off the pic for the plots so I regenerated the pic

[Phend]

Gen Z fixed what boomers had wrong all along.?

[duck_arse]

auto spellcheck might have turned an inverted omega for mho to the omega for ohms. you know how helpful those things are.

[Rob Strand]

I find it crazy how datasheets get more errors over time.  So much for iterative improvement and so much for don't touch what ain't broken.