Just got my opamps today. . .
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andrzejpw

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Just got my AD8620 and AD8610s in the mail today. Now, a few questions:

I understand I need one of these if I want to use the AD8610.

http://brndog.com/SingletoDual.html

Now, I see 8 places for legs in the picture. Where do the other 8(for the other opamp) go? How does one of these work?

Is that ALL I need for the opamp to work in the meta42 board?

Secondly, what's the best way to solder the opamps to the adaptor? I mean, it seems like if I'd bring the opamps into the sunlight, they'd burn up. When were talking about a soldering iron. . .

I'm going to buy a new soldering iron from radioshack from this. Our old one is pretty crappy. My dad says we'll need a 25-30w iron. Can anyone suggest any? Preferably from radioshack?
 
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puppyslugg

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Quote:

Now, I see 8 places for legs in the picture. Where do the other 8(for the other opamp) go? How does one of these work?


One is mounted top of the adaptor, and another is mounted on the underside of the adaptor.
Quote:

I mean, it seems like if I'd bring the opamps into the sunlight, they'd burn up.


They're not that fragile.
 
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zbuddah

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so if i understand this correctly... I would need two 8610's or one 8620's for it to work on the meta42?

and for the 8610's i would need the single to dual adapter, exactly like the one that andrzejpw linked to?

andrzejpw>

I thought you had to order in bulk to get the 8620's (like in the number of approximately 100)?

where could a lonely person like me get one?
 
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tangent

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The Brown Dog adapter has a little yellow pip next to pin 1 on either side of the adapter. The chip has one side with a beveled edge, which indicates the side with pin 1. If you put the chip on backwards, there's an excellent chance that you'll blow it up when you apply power!

The best way I've heard of to solder chips to these adapters is to use a clip-on heat sink to clamp it to the adapter, taking care to center the legs on the pads. The one Radio Shack sells should be ideal. Then you just apply a bit of solder to each leg. There's a balance here: too much solder and you'll bridge two pins, too little and you won't stick the leg to the pad. You'll figure it out after a little practice. This requires a somewhat fine tip on the iron, and reasonably thin wire -- 25 mils or so. If either is too big, you'll end up bridging pins. Should that happen, you'll have to soak up the excess solder with solder wick. If you leave enough solder behind, you won't have to apply more solder.

Quote:

Is that ALL I need for the opamp to work in the meta42 board?


Yes, the single-to-dual adapter will let a pair of AD8610s work in the META42. For your AD8620s, you need one chip and the standard Brown Dog SO-8 to DIP-8 adapter.

Quote:

I thought you had to order in bulk to get the 8620's


No, it's just expensive to order them one at a time, because Analog isn't geared to small orders. There's a $12 minimum shipping charge on all orders, for example. That means this one chip will cost you $24. It's because 1) they ship all orders in long boxes made for holding a few hundred chips in standard 20" tubes; 2) said boxes carry the chips in a big antistatic bag, which holds a complete 20" tube; and 3) almost everything ships from the factories in the Phillippines and Manila. By contrast, if you order one chip from Newark, they take the chip out of the tube, stick it in a small block of antistatic foam, and ship it to you in a small box from their warehouses here in the US. The overhead is a lot lower.
 
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andrzejpw

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can you guys recommend a soldering iron? Preferably at radio shack?
 
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tangent

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Why limit yourself? Here you are, about to embark on some delicate soldering, and you're telling us you only want to get a soldering iron from a company known to carry mediocre products. Don't cheap out on tools on this project.

Second piece of advice: search the archives here and at Headwize. The topic's been covered ad nauseam recently.
 
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mizterbob

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Question about ordering from Analog: I plan to build a META42 and want the ad8620. When I go to the Analog web page they require you to register, including all sorts of company info. Now, obviously I don't represent a company. What do you do, call them directly?

Also, would anybody like to combine an order to reduce shipping?
 
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andrzejpw

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Meh, do what I did. For Company put in "N/A"
 
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aos

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You don't have to specify company, having to do it often I just put "none" or "private" as the name, and as for industry and other company-related questions, I just put what the purpose of the chips is for, i.e. consumer audio etc. They'll be quite happy to sell to you regardless. Note that not all companies would do that, but Analog does, probably because of the hefty charges they tack on like shipping and the fact that they use workforce in their Asian factories to ship it so they don't mind if it's private order or not.
 
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