Library issue with 2N3819: Drain and Sources are inverted

Schematic Library Symbols
10

It’s a 2N3819 did I mentioned? Even if I didn’t tell: its blatant from the datasheets.

11

Ah this occurred already indeed :smiley:

12

Yes I watched the datasheet from the supplier. While the datasheet used to make the component library was different.
I discovered this AFTER 5 PCBs were manufactured and delivered with welded components … being for microphone, it’s better each pin is correctly connected.
ON the datasheet of that particular JFET is not written is flippable :-/

13

Many, but not all, jfets are symmetrical source - drain, so flipping would have no practical effect.

14

…; yes but in these cases it’s reported on the datasheet (like the 2SK170). I didn’t see it on the 2N3819.

15

Back in the mists of time, I had a jfet databook that actually showed the (small number of) die from which the various jfet types were selected during packaging and test.
I am fairly sure that the 2N3819 was one of the symmetrical parts. Identical Vdg and Vgs ratings are a hint.

1 Like
16

It was Nat Semi. This book was important back then in the 70s…

1 Like
17

Trust me when I say trust no-one. :thinking: :crazy_face:

But seriously feel free to submit a new symbol 2N3819_SGD and the minority one can be renamed 2N3919_DGS.

18

Tell me where to send new symbol etc and I will prepare it.

19

Gitlab, KiCad library, merge request. But don’t you need some anti-gitamine first? Or was that the other guy? :thinking:

20

Yes from the Die it seems very symmetric indeed

21

What sorry? I don’t get it.

22

Only if you are allergic to git.

23

I’m not allergic to Git. I do use GitHub on daily basis and I already released the EDA500 template for KiCAD.

I’m allergic to the no-yet-fully-working Git included into KiCAD for the time being. I hope it will be fixed very soon. Not to attend a major release but also in a minor release.

24

Ok that was the other guy then. So you know what I mean by MR on the symbol library containing 2N3819.

25

Ok I will do it there … inside the official library then. Perfect.
Just a thing: the flipped one already present is just called 2N3819. How would you suggest to call the one I will do? 2N3819F? (flipped) 2N3819THE_BEST? Any idea?

26

2N3819_SGD. There is precedent for this, some symbols are suffixed, by for example EBC, indicating the pin order of the terminals.

2 Likes
27

Ok I will follow this suggestion then

28

I added it /merge_requests/4934

1 Like
29

However it wasn’t merged. So: no point :-/