We have been having some issues recently with a TSOP-II 54 pin, where upon second reflow the part will lift at end one, most of the time the solder will pull up with it and still connect but I still worry about strain on the component as well as it isnt good practise to allow these things.
As we are small scale (at the moment) we have to send our PCBA through re-flow twice when dealing with double sided assemblies. On first re-flow the TSOP54 part will solder perfectly without any issues. When on the second re-flow this part will be upside down but supported and one end will lift where it looks like the part will bend slightly. no other components are affected in anyway just this one (also have a TFQFP176 as well as some 0603 caps and resistors)
Changing direction we send the PCB through the re-flow oven seems to reduce the amount this happens or if it still occurs it lessens the height the component will lift but doesn't eliminate fully.
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