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W07VH5 |
I have these tiny parts that I can barely see:  The data sheet says "the pin one indicator is in this shaded area" but it doesn't say what the indicator is. There is a printed dot, that looks more like a copyright symbol, and a printed line on opposite ends that would indicate that pin 1 could be on either end. The dot looks more like a dot in the thumbnail pic but up close the line looks more defined. Here is a closeup:  Any idea what the correct indicator is or should I just solder them in and try it both ways? | ||
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Unflappable Enginerd |
I don't think that is a "copyright symbol", I'm pretty sure that's a molding mark to indicate pin #1, could be wrong. I HIGHLY recommend against "try it both ways", you'll probably let the smoke out.  Everyone knows the smoke is what makes electronics work... __________________________________ NRA Benefactor I lost all my weapons in a boating, umm, accident. http://www.aufamily.com/forums/ | |||
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Nullus Anxietas |
Identifying pin no 1 on an IC "America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe "If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher | |||
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| W07VH5 |
Well, I'll be. I didn't even notice the bevel. Mostly because it's microscopic and partly because I didn't know to look for it. Thanks. Text direction, a dot-ish mark and a bevel is three against the line so the line loses. | |||
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| W07VH5 |
Those little beauties are like $7 a piece so I don't want to let the smoke out.  | |||
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| Nullus Anxietas |
Handling bare ICs like that: You are using appropriate anti-static measures, I hope? "America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe "If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher | |||
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| W07VH5 |
I have a grounded anti-static mat. | |||
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| Nullus Anxietas |
You need to be wearing an anti-static wrist band, connected to the mat, as well. Something such as shown here: SCS 746 And the mat needs to be grounded with a similar cable. N.B.: Those cables have high-value resistors built-in. They ARE NOT low-resistance connections. Using just wire would create an electrocution hazard. Modern ICs are so-densely packed, the internal components so small and the paths between them so short, it takes very little ESD to impair or destroy them. "America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe "If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher | |||
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| W07VH5 |
I have an anti-static wrist band ... somewhere around here. | |||
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| W07VH5 |
I should be more concerned with the moisture sensitivity of these things. I moved them to the safe by the heater until my PCBs come in. | |||
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Political Cynic |
the dot indicates Pin 1 for orientation | |||
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| Nullus Anxietas |
Static is a far bigger issue than moisture. If you have that wrist band and the proper cable to go with it, I strongly advise you find and use them. I won't even take a populated PCB out of its static-resistant or anti-static packaging w/o first deploying a mat, putting on a wrist band, and tying mat, wrist band, and item under repair/upgrade/assembly together. You would be amazed at how much static electricity can be generated with the most innocuous of movement, and it doesn't have to be nearly enough to generate a noticeable spark to cause damage. "America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe "If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher | |||
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| W07VH5 |
The packaging says to bake them for 24 hours at 125° before soldering. I've never worked with SMD before. I've also never had to worry about popcorning a component. Just trying something new. | |||
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| W07VH5 |
My PCBs arrived today and I successfully soldered two OPA1612s in with a soldering iron. Next time I'm going to try the solder paste in a toaster oven. | |||
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