Screaming Circuits: Components So Fragile, They Break Before Arrival

PROTOTYPE AND SMALL VOLUME
PCB ASSEMBLY MADE EASY

Components So Fragile, They Break Before Arrival

There are a lot of components that require special handling. Some days, "special" requirements seem more the norm than the exception. But, every now and then, we see something that puts even those special components to shame.

Not long ago, we received a parts kit that contained a component so fragile, that most of them didn't survive the trip with the shipper. It's a 10 mm x 9 mm (well, actually 9.68 +0.00/- 0.08 mm X 8.64 +0.00/- 0.08 mm, to be precise) sensor that's only 0.05 mm thick. That's 1/4 as thick as the diameter of the solder balls connecting it to the PCB.

Broken image sensor tilted

The part has solder balls on the silicon, with no other packaging. The Dice has to be that thin, as the light sensitive area is on the other side. That doesn't make for a very robust component. It would require special handling all around. Unfortunately, no matter how careful we might be, if they're broken when we receive them, there's not much we can do (other than take pretty pictures).

In taking these closeups, I noticed that the registration in ball placement isn't all that great. In the following image, take a look at the ball on the left, second from the bottom, and the ball on the far right.

Broken image sesnor corner 800

The data sheets calls out all non-specified tolerances as +/-0.001 mm. With these being 0.2 mm diameter solder balls, I'd have to say this is way outside of that tolerance. I'm sure the part would have adhered to a decent PC board just fine, but if the PC board were off a similar amount in the opposite direction, you may very well have a problem.

Duane Benson
You could make a very tiny sundial out of this.
But, could you use the shadow parallax to calculate the distance to the sun?

Comments

Wonderful post.This is nice post and provides full information. i prefer to browse this post as a result of I met such a lot of new facts concerning it really.Thanks loads. I bookmark your web log as a result of I found superb info on your web log, Thanks for sharing.

Post a comment

If you have a TypeKey or TypePad account, please Sign In.

« What's So Difficult About Diodes? | Main | Never Take Pin Numbering For Granted »