ExpressPCB footprint widths

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The ExpressPCB footprint for a 0603 chip is slightly narrower than the chip and the overall length is only slightly longer than the chip.

Panasonic's datasheet says the narrower width is proper for flow soldering but for reflow soldering, the land should be the same width or slightly wider than the chip.

I don't know the difference between flow and reflow soldering, but a little wider and longer should make it easier for me to place and solder the chip with an iron.

I like big pads so my iron can hit the pad without hitting the chip. I'm thinking of making a footprint with bigger lands.

On the other hand, these lands might be good if I was to use hot air. I have hot air on my soldering station but I've only used it to shrink some heat-shrink tubing. It works great for that. :) I'd like to try it for soldering sometime.

Do you guys use hot air or an iron?

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I have a tendency to make my pads slightly longer for soldering. I use Target3001 for up to 8 layer boards. I've built up the libraries over the years and almost all of the stock footprints have been tweaked for this reason you bring up.

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You figure the footprint was designed for solder paste not for manual solder iron. Make 2 footprints...one for proto and one for production if you have to.

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pad sizes really do come down to preference - there really is no absolute right or wrong. as long as you're in the ballpark, they'll work fine.

Wave soldering is maybe a bit more necessary to have the dimensions right, but even then.. there's still room to move.

Bottom line - if you want pads a certain way, then make them that way. and then if you're unsure - post up your dimensions and ask people if that should work or not - chances are, it will.

I have a set of my own "standard" SMD pads that work fine for reflow (in contract manufacturer's reflow ovens, and with a hot air iron here) but also have enough space for soldering with a conventional iron.

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Thanks guys.