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840AV identify missing IC @ U9

Bama

Well-known member
Hello All,

I need your help to identify the IC part number located at U9 on my 840AV logic board.  I recently purchased this 840 from eBay as not working and I started removing the leaky SMT electrolytic capacitors.  I discovered that the IC at location U9 is missing.  Bomarc schematics appear to have it as part of the analog sound circuit for the headphone output.  I have uploaded a picture of its Empty location.   Please share it’s part number, so I may purchase a replacement.

Thanks,

Bama

D49074FB-6BC0-4745-9899-3D38FF45E7B3.jpeg

 

Bama

Well-known member
I decide to upload a better picture to more clearly display the location.

If you have access to a 840AV, please upload a picture of the IC at U9 with the part numbers visible or if you are savvy then please recommend a replacement or where to learn the data for this missing IC. 

:)

Bama

4E10DED4-9197-4570-947A-8BF470C2E6FF.jpeg

 

Bama

Well-known member
Newbie alert!  

I need your help.

If you are adept at reading schematics and choosing compatible parts, then please share your opinion on U9 in the schematic and the proposed Op-Amp data sheet image.  Maybe this sparks a memory of the correct part number...maybe you saw this on another vintage Mac?  

My Google searches for "Macintosh op-amp""Quadra Op-Amp"or operational amplifier....nada.  Searching google images for 840AV and other vintage Mac logic boards only yields blurry pics of 8-pin IC's.  

Thanks for reading another post in the saga.

:)

Bama

IMG_26AD8E02BDA0-1.jpeg

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cheesestraws

Well-known member
The schematics do show it as an op amp so that looks perhaps reasonable?  I was confused by the curved back of the op amp on the schematics, but I just found a footnote in a book on them that suggested that that's just an old way of drawing the symbol, and doesn't actually mean anything special.  Also, the pin numbers on the schematic line up with that diagram of the TLE2082 from the datasheet.

So in the absence of any other info, I'd give it a go, personally.

 
Last edited by a moderator:

jeremywork

Well-known member
I just dragged this one in from ebay, it needs some attention to say the least but confirms your part number. 

9FE620B0-365B-4DE8-83B8-F3FC73BB5B40.jpeg

 

Bama

Well-known member
Awesome, thanks y’all!!!

I will purchase the that IC and some replacement capacitors and cross my fingers!

:)

Bama

 

Phipli

Well-known member
Bit late to the game sorry :) Just sharing a picture to give a bit more info to verify. Besides, I was stood right next to a bare 840 board when I read your post.

IMG_20201004_175450.jpg

 
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