2SC1849 Transistor Pinout?

[Steve Mavronis]

I just got the remaining parts I need including the 2SC1849's from Small Bear. My father is going to e-mail me instructions later on how to make a transistor tester to determine NPN or PNP and where the emitter base collector is. In the meantime, I know these are NPN transitors but can anyone confirm the pinout? Here is thow the 2SC1849 is labeled on the flat side:

C1849
R   50

Here's an illustration for how my MPS5172 NPN transistor is mounted. This is why I need to figure out the pinout for the 2SC1849 that I just got to be sure:



[EDIT] I just found this Asian datasheet on the 2SC1849 / 2SC1850 - http://jp.ic-on-line.cn/IOL/datasheet/2sc1849_951106.pdf

If this is true to the ones I got from Small Bear then I am safe with my PCB layout. Can anyone confirm if they also got some from SB too?

[Steve Mavronis]

Well I did some testing on the 2SC1849 using a digital meter in diode test mode. I read how the relationship of the emitter to collector is such that the voltage drop is 'slightly greater' between the emitter and base than between the collector and base.

First though I used a simple diode test to verify that the leads on my meter were positive and negative as labeled. Then I determined where the base was and that it was an NPN transistor. I don't want to go into all the details here but learned how by watching several YouTube videos and reading websites like this one - http://www.allaboutcircuits.com/vol_3/chpt_4/3.html

Refering to the pinout number order in the graphic below with the postive (+) base already determined to be in the middle, and using the negative (-) lead testing the voltage drop between pin 1 and 2 was 1.025 and the drop between pins 3 and 2 was 1.014 making pin 1 the emitter side. This behavior was also verified with known NPN transistor MPS5172 that has an EBC configuration that measured E=1.038 vs C=1.030 using the digital meter diode test. The difference between E and C isn't much but it was consistant every time.



Anyway I hope my test method is good enough to go with, otherwise you're invited to my transistor BBQ!

[tubelectron]

Hi Steve Mavronis,

According to my book "Répertoire Mondial des Transistors - 3e édition / 1980", the 2SC1849is described as follow :

NPN si TO92 pinout=L21, which is not the same as the 2N5088, 2N3904 (pinout=L14) : instead of EBC, you have ECB on the 2SC1849. So, according to your figure, you have :

1=E
2=C
3=B

A+!

[Steve Mavronis]

Instead of EBC, you have ECB on the 2SC1849.

But on the set I got the middle pin 2 is definitely the Base. When I measure between pins 1 and 3 it doesn't conduct. It only conducts between pins 1 and 2 and between 3 and 2. I'm pretty sure my set of 2SC1849 transistors match this datasheet on the 2SC1849 / 2SC1850 - http://jp.ic-on-line.cn/IOL/datasheet/2sc1849_951106.pdf

And being NPN the base is positive and the emitter and collector are negative ends. I'll double check with my dad's 'real' transitor testor this weekend when I give him my enclosures to drill from my template.

[zombiwoof]

My meter has a transistor checker, I can usually find the pinout just by inserting it in various combinations till I find the one that works and note the orientation.  However, I sometimes use the NTE Cross Reference, and it shows EBC with the flat face towards you for that transistor:

http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/69d5aa3584d015ce85256e780056e56f?CreateDocument

Of course, NTE points you to their replacement for the transistor in question, but if their equivalent has a different pinout than the original they will note it on the data sheet.  In the case of the 2SC1849, their replacement is the NTE123AP, which has the same pinout.

Sometimes, a transistor will have a different pinout depending on the suffix.  An example is the BC183, which has a different pinout than the BC183L.  Maybe that is the case with the differing results some people are reporting for the 2SC1849.

Here's the main page for the NTE Cross Reference:
http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/$$Search?OpenForm

Al

[tubelectron]

Hi again Steve,

Yes, there may be a doubt : I found a datasheet http://www.datasheetcatalog.org/datasheets2/41/41034_1.pdf which seems to display the EBC pinout and not the ECB, and so you may be right. So my book may be wrong (it sometimes arises...) or it is a different pinout depending on the suffix, as pointed out by zombiwoof ofr the BC183/183L. Your Transistormeter will tell you the truth, then !

A+!

[Steve Mavronis]

FYI, I got an email reply from Steve at Small Bear Electronics where I bought my 2SC1849 transistors:

Looking at the front with the leads pointing down, from left:  E  B  C. Same as your drawing.

[tubelectron]

FYI, I got an email reply from Steve at Small Bear Electronics where I bought my 2SC1849 transistors:
Quote
Looking at the front with the leads pointing down, from left:  E  B  C. Same as your drawing.

You're right, Steve. I cross-checked with an another book of the same era : TVT Transistoren '80/81, and yes again, I confirm that it's EBC, not ECB, so my previous assertions were wrong, so is my  "Répertoire Mondial des Transistors - 3e édition / 1980" for 2SC1849.

A+!