OK, if you're going to stuff high-dissipation parts into absurdly small packages, power pads are a good idea.
ftp://66.117.156.8/PowerPad2.jpg
(at least it's hard to bend the pins)
But why do only a tiny minority of datasheets mention what the pad is, or isn't, electrically connected to?
John
That's one of those rhetorical questions, innit?
I'd guess it's going to be the substrate, if anything, but that and two bucks will get you a cup of coffee.
Best regards, Spehro Pefhany
-- "it\'s the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
It was a whine.
Seems like very roughly half are insulated, either by a di semi process, or some sort of actual insulator. And the rest seem to be mostly substrate, so must be floated or strapped to the most negative chip supply. For the ungrounded cases, one must find a way to conduct the heat out of the board from what may be a small pour.
A small latte is up to $2.75 here, but worth every devalued cent.
John
Call me paranoid; even if the vendor DOES spec slug connection, I do an ommeter check....
W Letendre
A fellow paranoic. I do, too.
John
If your power pad is whining perhaps there's a problem with your paste mask. ;-)
-- Ben Jackson AD7GD http://www.ben.com/
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.