Thanks for the input. I dont have a component specific stencil thus, cannot paste the lead pads. I would apply no clean flux to the pads on the PCB and dispense a dab of paste on the ground pad of the PCB.
>>When these boards are built new do we not have solder >>paste on the ground pad and then reflow? Has this caused >>any misregistration for you? We didnt assemble these boards so I have no knowledge of the manufacturing process that was implemented however, paste was cerainly applied to the ground pad. This is the primary reason why I think a reflow profile should be such that leads reflow first followed by the ground pad.
As far as using a higher melting temperature solder paste for the ground pad, it certainly sounds logical. My concern would be to keep the package temperature below the danger mark of 250 deg.C. Also, the component is originally reflowed using 63/37 alloy at both the leads and the ground pad . . . so there is a proper technique, I am just not sure about it. The problem is that I don't have ample parts (PCB's and components) to find a solution. Two trials at the most, and we must get the technique down.
>>I would bet (probably lose) that if you just stick that >>part on with the leads aligned that you are going to be >>fine. I think you might be right. Hopefully, my profile is such that the leads will reflow first and once the ground pad reflows, it will not shift the part out of alignmnet.
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