I am now at the point with my lightning detector(s) to design my own board. The requisite chip (AS3935) is an MLPQ, which is very similar to the QFN with a central heatsink and ground plane connection.
Recommended layout (http://cds.linear.com/docs/en/packaging/Carsem MLP users guide.pdf ) is to use "non solder mask defined" pads (NSMD pads). That is, don't put solder mask between the pads. The alternative is "solder mask defined pads" (SMD pades) which has each pad separated by a microscopic line of solder mask. I understand the argument for using NSMD pads when doing reflow soldering.
My plan is to hand solder the chips, which are 16-pin, 4 mm x 4 mm with 0.65 mm pad spacing. Does anyone with experience have a recommendation for which type of solder mask to use? I have experience using larger leadless packages and simply heated the pad and exposed lead on the side of the package while wicking the solder under the device. It seems to me that with hand soldering the solder mask define pad might be preferable as it should help avoid bridging under the chip.
My solder is 63/37 tin lead 0.015 with rosin core.
John
Recommended layout (http://cds.linear.com/docs/en/packaging/Carsem MLP users guide.pdf ) is to use "non solder mask defined" pads (NSMD pads). That is, don't put solder mask between the pads. The alternative is "solder mask defined pads" (SMD pades) which has each pad separated by a microscopic line of solder mask. I understand the argument for using NSMD pads when doing reflow soldering.
My plan is to hand solder the chips, which are 16-pin, 4 mm x 4 mm with 0.65 mm pad spacing. Does anyone with experience have a recommendation for which type of solder mask to use? I have experience using larger leadless packages and simply heated the pad and exposed lead on the side of the package while wicking the solder under the device. It seems to me that with hand soldering the solder mask define pad might be preferable as it should help avoid bridging under the chip.
My solder is 63/37 tin lead 0.015 with rosin core.
John