Packaging Engineers
 

These wankers are making it harder and harder to put these ICs on without expensive equipment.

It took a bit but I finally worked out a way to get these buggers on by hand soldering. This pic is magnified x40 and I've got to work under a microscope to do it. No wonder my eyesight is failing....

http://forums.pelicanparts.com/uploa...1324526392.jpg

Yeah,

Amazing isn't it!

Long gone are the days of using a simple soldering iron. Now one needs a hot air reflow setup minimum. It's good for the small parts but then there are the high pin count fine-pitch BGAs which, trying to do those manually with a simple hot air reflow is almost impossible without a high fall-out. SOA BGA hot-air reflow stations require selling both your nuts plus a nut from someone else.

packaging engineer? i thought a pack eng builds those damn plastic containers that are damn near impossible to open?

How did you do it with an iron?

EDIT: I see. the pads extend beyond the part. Tin the pads, balls and apply pressure.

Our techs use some sort of hot air device. It's probably expensive.

I'll bet you could makeshift something smaller using a hot air gun designed for heat shrink tubing. It has a slower airflow and hotter temps than a hair dryer. Then you make some metal adapter tips for the end to shape the airflow for the size and shape chip you are doing. Perhaps a laser temp gauge would let you know when you got the right temps without exceeding the chip limits.

What is that? A 3x3? Be happy it wasn't a bumped die!

How much for the tintype of the cow with buck teeth?
Jim

It's a whopping 4x4 LGA package! I did the pcb design, so I've only myself to blame for it being there. I had some other bonehead do the assembly, but he cooked this device good and proper (and a few others). The pic is after I removed the dead device.

Like most things, to get them on it's all in the prep work. Clean between each step and use plenty of flux. Soldering iron used to 'bump' the pads on the package with solder, and localised hot air on both sides of the pcb to 'reflow' it back on. If you can get the position close (hence the microscope), these devices tend to self locate when the solder flows. This pcb's a prototype, so I designed the land pattern so that I could get it on manually. It'll be a slightly different land pattern for an automated process (if it goes that far). It's also a multilayer pcb with most of the internals being heat robbing copper planes - doesn't help the manual assembly process.

Manual hot air assembly devices are relatively cheap in comparison to mini reflow/IR ovens and paste machines.

SmileWavy

Hehe...I didn't see it at first. Well spotted :D

Aren't they also a pain in the bum. I always end up cutting myself on that stuff

Yep. I have to send anything I design with BGA's away for assembly and x-ray inspection.