Address,
     
     I asked this question once before but probably didn't send correctly.  
     Is there anyone out there currently assembling chip resistors 
     underneath a J-leaded PLCC-44?  IPC-SM-782 does not spec the contact 
     lead to package distance.  I may be placing any of following 0603, 
     0805 and 0402 under the PLCC-44.
     
     Concerns I have:
     
     Without running a Thermal Profile with thermocouples will there be 
     enough heat to reflow the underlying chip or will the PLCC-44 device 
     rob it of heat?
     
     I'm I correct to assume the chip may crack should the pressure from 
     the head be too strong and obviously if there is enough room under the 
     device.  The assembler does not have a variable pressure control for 
     pick and place heads.
     
     And again is it feasible.  I have other options but none that are as 
     efficient as the one described.
     
     Please advise,
     
     John Gulley - QA
     
      

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