[Nisbeth]

This might be a stupid question but I can't for the life of me find anything on any of my AD86x0-opamps that indicate pin 1 and the datasheet isn't much help as far as I can see. Which rule of thumb/part of the datasheet did I overlook?

/U.

 

[JMT]

The "top" of a chip is usually marked with a physical notch in the chip, but in the case of the AD8620 there is a "painted" notch. Orient the "notch" so it is at the top, you will have 4 pins on each side. Pin #1 is in the upper left hand corner. Pin #4 in the lower left, pin #5 upper right, and pin #8 in the lower right.

 

[Nisbeth]

Thanks, I was right all along then

Why the h#€%& can't AD just mak a proper notch in the case like evrybody else?

Idiots!

/U.

 

[morsel]

Before you rake AD over the coals, did you look at the pdf? There are at least 2 ways of determining the orientation of the so8: the bevel on the pin 1 edge, and the orientation of the text with pin 1 in the lower left corner.

 

[Nisbeth]

I did look at the datasheet, but to be honest I didn't find it very helpful. I had the painted "dot" pegged for being the indicator but I wasn't sure.

I could have just gone with my best guess, but I have tried making "split second decisions" like that before and I am almost always wrong

(I could of course have tried to capitalize on this and done the reverse of what I originally thought and then tried it, but....

)


/U.

 

[tangent]

The bevel on the side of the chip seems to be a near-universal standard for SOIC. The next most common is a shallow divot in the top surface of the chip near pin 1.

 

[Nisbeth]

Well, after studying the thing very closely I have to (grudgingly) admit that there is a dimple in the casing near pin 1

Oh well, I guess I learned something today anyway

/U.

 

[Voodoochile]

The little divot shows up in this pic.
I sometimes use a little penlight at a very low angle to the chip to helps find it. The hard shadow makes the bevel and divot really show up well.

 

[Nisbeth]

Well, the problem wasn't that I couldn't see the dimple but rather that I didn't know what to look for

Thanks for the pic though

/U.

 

[peranders]

Look at the datasheet at page 17 at upper right. There you have the answer.

 

[enzoferrari650]

I fried my ad8620 guessing which side is which...... it was probly my unlucky day.... lol oh well, 50/50, i guess thats a prett big chance of putting it in wrong.