Advice for soldering AD4030-24 BGA package

[Jacques]

I'm building a handful of measurement setups that employ the relatively new AD4030-24 ADC from Analog Devices (these are to be operated in our small R&D lab). This is the first time I'm using a BGA package in a design and I'm left with a couple of questions that I hope some of the more experienced members here can shine a light on.

• The datasheet doesn't mention anything about the solder ball material, nor does it include some sort of recommended reflow curve other than a maximum package reflow temperature of 260 degrees Celsius. Where should one find this information?
• I have access to a small vapor phase reflow oven in the lab. Given the use of that particular reflow process, what would be the preferred approach to solder this IC to the PCB? From what I’ve read, one option would be to apply some tacky flux to the PCB, place the IC in it and then just let the oven process it. Is this indeed a reliable approach? (Some people seem to apply solder paste to the BGA pads instead, but I only have leaded solder paste right now.)

_{P.S.: first post here, please be gentle}

[coromonadalix]

normally  for bga, you use a stencil with a fine grain solder paste, the finer the "grain size"   better it will solder

you have tons of google videos on how bga are soldered on pcb, reworks  etc ...

[Echo88]

If i remember correctly i also used solder paste when soldering my AD4030-24-testboard with success, while using a suitable reflow profile that was based on the suggested solder paste profile. In my case https://de.beta-layout.com/download/rk/RK-10753_824.pdf page 10

[thm_w]

https://www.eevblog.com/forum/manufacture/home-fab-with-bgas/

[tooki]

• The datasheet doesn't mention anything about the solder ball material, nor does it include some sort of recommended reflow curve other than a maximum package reflow temperature of 260 degrees Celsius. Where should one find this information?

Surprisingly, I couldn’t find any specific document for your device’s package. (By googling “ analog devices csp bga reflow” and similar.)

But between these two guides you should be able to come up with something:

https://www.analog.com/media/en/technical-documentation/product-information/assembly-considerations-for-module-bga-packages.pdf

https://www.analog.com/media/en/technical-documentation/application-notes/AN-617.pdf

(As best I can tell, your IC is built using the technology of the latter, but in the dimensions of the former.)

normally  for bga, you use a stencil with a fine grain solder paste, the finer the "grain size"   better it will solder

Not necessarily true. Finer solder (≈higher “type” number”) ages more quickly, and is more susceptible to forming solder balls on the board. So you really want to use the coarsest paste that works with your stencil apertures. Both of the ADI documents above suggest type 3 (which is the “standard” type) or type 4, not the finer types, even for the fine 0.4mm pitch devices. The device here is 0.8mm pitch, so no reason at all to go fine.

[Jacques]

Thanks for the input, everyone. I decided to just give it a try using only tack flux and no extra solder paste, as shown in the following video, with the default lead-free solder profile set on the reflow oven:

I verified the BGA soldered correctly with the trick featured in the video, testing for the expected diodes across the digital and analog inputs of the BGA and making sure there are no shorts between the various power pins and ground.

All in all, that went a lot smoother than expected.