TMS320C6678CYPA mechanical packaging

Is the TMS320C6678CYPA a POP (Package On Package) chip?

No, it's not a POP chip.  Here's an article that should cover your original listed concerns http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=04012674

Basically, it's done this way for cost savings.  This is a flip chip design and the balls of the die are mounted on the substrate are encapsulated with an underfill so the only exposure of the die is it's topside/outside and no exposure is to any sensitive area's occurs. 

As for the purpose of the 3 layers - Substrate  is required to be able to provide ball sizes with spacing required for customer board layouts - so this is larger than the die as is common.  The Die is of course the actual Si.  And the Top is a thermal slug to maximize heat dissipation.

Best Regards,

Chad

Appreciate your reply or confirmation if the Flat Lid is connected with miniature metallizations at the four corners as they appear to be copper exposed.  If not in four corners of connection, will that mean a single flat lid preformed to these edges as delivered.  Thanking you for your confirmations.  Warmest regards!

I'm not sure I fully understood your question, but I'll try to give you the information that I think you're looking for.

The Lid is attached to the die with a thin layer of thermal adhesive.  It also has four stand-offs that are oblong in shape that are used as both support and attachement between the Lid and the Substrate.  This is done to help ensure the lid isn't accidentally broken loose during heat sink installation if too much pressure is applied while off center.

I'm not sure what miniature metallizations at the four corners you're referring to, or exposed copper.  Maybe you're referring to the corners of the die which you can see, when looking towards the center from the perspective of the corner in between the lid and the substrate. 

Best Regards,

Chad

Hi Chad,

Thanks for the reply. I also have the same concerns regarding the 4 corners of the chips being exposed to ambient surrounding. Won't the chip suffer oxidizing effect or is the die covered internally and separated from the surrounding air. If that is the case, wont the heat dissipation be affected as the chip is covered up.

Another concern is if we subject the chip to vibration, will the oblong sidewall be strong enough to withstand the vibration and not break loose from the chip.

Thanks for answering the query.

Okay, thanks for the assurance. W e will conduct the test ourselves. Thanks.

1. The HTOL (High Temperature Operating Life) Test documents and the MTBF figures. In TI website, the status is still TBD.
2. The environmental qualification tests report of C6672/ C6678. (Thermal Shock, Temp Cycling, Vibration, etc...)