In a project I used the 2N3904.
It was delivered with B and E inverted.
I checked out and I found numbering where correct (on the schematics and Datasheet
But unfortunately the SOT-23 available on KiCAD has the B and E inverted … the 1 pin should be at the place of the 2 and vice versa … It should always be named 1 and E and the … just in the geometry must be inverted.
2N3904 check the first screenshot is Fairchild … and JLCPCB mounted them … (second screenshot … KEC … 2N3904 … not MMBT
I solved flipping them upside down and resoldering … now I just readapted the PCB and I created a custom Footprint.
HOwever I will be not the only one with this issue if not better specified or corrected.
I don’t understand the problem source. 2N3904 in SOT23 has connections as most of transistors at market. They only untypically numbered pins in their datasheet but it is only paper.
For me most typical transistor I use is:
For you is only paper. For the reality on field, there are 2 pinouts … Not only I showed it, but as I said: 5 PCBs were given with the pinout of FAIRCHILD and not the one of KiCAD. What should I say more? just what it’s into the library, is NOT sufficient to cover all the cases.
Indeed, but MOST cases are covered. I failed to see a suggestion that could help us though. I can suggest further to contribute missing symbols yourself. (same way all others got there)
( I really doubt that all cases can be covered by a relatively small team of volunteers. Manufacturers helped enough already. )
SOT-23 comes with all possible permutations. Not only for transistors but also for diodes. Since then I always check the data sheet. Sometimes a board has 2 different sot-23 footprints, each with a different pin numbering.
If symbol was not compatible with footprint than I would expect information how both were chosen and why that they were not compatible.
I have KiCad V5 with KiCad libraries (V7 I have with my libraries and second PC is Win7 so KiCad V5). I have looked into V5 libraries and now I suppose I understand. There are many NPN symbols to chose from.
Fortunately transistor has only 3 pins. What would be if someone would like to have penthode symbol with all pin numbering combinatons
But it is good that there are so many symbols. You see that there is a problem to be checked.
Each manufacturer can have its own pin numbering standard. The problem is to select compatible symbol and footprint.
I understand that you want transistor symbol with all pin combinations and SOT23 with all pin combinations. It makes 6 NPN transistor symbols and 6 SOT23 symbols. Then PNP, MOS, JFET, double diodes and even LDOs. Each with all possible combinations.
It will not solve the problem but only generate bigger mess.
Your transitor has pins:
C
B E
In KiCad V5 footprint libararies SOT23 has pins:
3
1 2
And from KiCad V5 symbol library transistor symbol Q_NPN_BEC can be used so KiCad covers 2N3904 case.
I don’t suppose this symbol disappeared from V7 library.
A picture you showed with both pin number and pin name in pads (I suppose it is while you select footprints for symbols what I have never done so I have never seen it) is to help you to check if everything is correct. In datasheet you have a photo with BEC identified so it is very easy to check with what KiCad shows (I remember people postulating it so it is probably since V6 or V7).
Now it looks that it is also not enough. What else KiCad can do?
What is 06?
Does it mean that it is transistor with B and E swapped?
I must be blind. I have read the thread once more and I can’t find that 06 nowhere.
I don’t understand.
I supposed that in your first post at right there are two pages from the same datasheet. Now I see they come from different datasheets. But in both datasheets transistor has the same pinout:
----C----
B-------E
(I see that in my previous semi pictures all spaces were reduced).
OK.
I have some transistors with the same name as the basic one (don’t remember it was 20+ years ago) but with addition of letter ‘R’ (for reverse). The transistor with ‘R’ is the same (electrically), but has B,E swapped.
I all the time supposed that you have got 2N3904 with B,E swapped.
And now supposed that may be it was marked by adding 06 at the end (I read ‘and’ as ‘end’).
I don’t know KiCad libraries. I supposed that you selected from ‘Devices’ library wrong NPN symbol or they assembled transistors with reversed B,E.
But all information till now showed me typical NPN pinout.
Now I suppose that there are in KiCad library 2N3904 symbol with wrongly numbered pins and it is the problem.
If so then 2N3904 symbol simply is to be corrected.
I suppose the symbol is wrong.
As manufacturer can select his way of pad numbering KiCad also can.
As Kicad decided to number pads one way it should use the same numbers in 2N3904 symbol even manufacturer used different numbering.
