choosing package of IC

[senmeis]

Hi,


the bare die must be packaged to become an IC. My question is if there are favorite packages (QFN, BGA and so on) for specific ICs such as PA, DSP and so on?

 

[barry]

Generally, it’s pin count that drives the package. There are other factors besides the function that determine package, that’s why manufacturers give you choices. BGAs are more difficult to solder and debug, so you may not want to use one if you don’t really need to. But BGAs are more compact, which means they’re better for higher speeds. Power dissipation also figures into package selection.

 

[dick_freebird]

Package parasitics are the big deal for RF
products. Not only must they be low
inductance and inter-lead capacitance,
the values must also be well known
(modeled) and controlled as they are
part of port matching. Generally favoring
small and short leads, but potentially
needing to accommodate heat slugs etc.
at some compromise to size.

Customer "pull" probably defines the
packaging for many applications - super
thin is in, for phones; automotive wants
the most durable with extended temp
range; many military systems still call
out hermetic (as a consequence of
demanding certain bundles of test /
qualification).