Help identify R 25 r 47, IC markings?

B

Barry Wilkins

New Member

• Jul 30, 2011

• #1

I am in the process of repairing one of my DS0,s there are some surface mounted devices on the pcb board ,think they are SOT 23 .
One is marked as R25, and says its Q3 ,but it is not a transistor ,elsewhere another one is marked as D.
Does any body know what exactely these are ?

Barry Wilkins

 

alec_t

Well-Known Member

Most Helpful Member

• Jul 31, 2011

• #2

Can you post a clear close-up pic, and/or the relevant part of the DSO schematic, to help us? How do you know Q3 isn't a transistor?

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Jul 31, 2011

• #3

R25 and R47 sound like resistors (0.25 ohm and 0.47 ohm).

 

mvs sarma

Well-Known Member

• Jul 31, 2011

• #4

R25 could be either 2SC3356S (SOT23)
or 2SC4226 (SOT323)

47 could be either BAS40-07 (sot143) A dual diode or
BAS40-07W (SOT343) again dual BAS40

i got these info from a SMD codes book downloaded recently.

 

Last edited: Jul 31, 2011

B

Barry Wilkins

New Member

• Aug 1, 2011

• #5

R 25 etc

I think these are some form of double diodes in a sm out line

 

B

Barry Wilkins

New Member

• Aug 1, 2011

• #6

photo

 

Attachments

• Channel 1 osc.png

  3.5 MB · Views: 159

alec_t

Well-Known Member

Most Helpful Member

• Aug 2, 2011

• #7

Having seen the pic, despite your assertion I'd put money on Q3 (R25) being a transistor. Didn't notice D on the pic.

 

C

cobra1

New Member

• Aug 2, 2011

• #8

Q3 IS A NPN Silicon Epitaxial Transistor
Device number: 2SC3356

Here is the datasheet to match it to another transistor.. https://www.electro-tech-online.com/custompdfs/2011/08/2sc3356_n.pdf