Display Your Know How: Thermal Relief

You could change the narrow trace to a bigger shape and change both to full contact. This way both sides would have similar thermal properties and the risk of tombstoning would be reduced.

Bonus note: If the component is a DFN type, the risk of tombstoning is not so big, because of reduced leverage on the terminals. Agree?

Gold star answer - thank you FalcomPeter !!

Agreed, changing the narrow trace on the right side pin of the surface mount component will help to balance the thermal properties of this part which will help production. You have rightly pointed out that the issue of tombstoning is of concern for discrete component types. This phenomenon describes components that lift on one side due to a timing imbalance of soldering between different pins. The finished PCB may look something like a graveyard if lots of "tombstones" are sticking up in the air indicating a dead circuit due to these broken connections.

It is caused when one surface pad heats up much faster than the other. The melted solder pulls on one side of the component due to surface tension and buoyancy. Without a counteractive pull from the other unmelted side, lightweight components will rise into the air. Videos of this phenomenon are available to view on public channels such as youtube. 

Question though: which side heats up quicker - the side with wider copper or the side with less copper? Remember the heat energy comes from the atmosphere.

Do you have any thoughts on the through-hole discussion? Any insights would be very welcome. One point we would like to mention is the assembly technique known as "intrusive reflow", Some manufacturing engineers also name it "pin in paste". 

Gold star answer - thank you FalcomPeter !!

Agreed, changing the narrow trace on the right side pin of the surface mount component will help to balance the thermal properties of this part which will help production. You have rightly pointed out that the issue of tombstoning is of concern for discrete component types. This phenomenon describes components that lift on one side due to a timing imbalance of soldering between different pins. The finished PCB may look something like a graveyard if lots of "tombstones" are sticking up in the air indicating a dead circuit due to these broken connections.

It is caused when one surface pad heats up much faster than the other. The melted solder pulls on one side of the component due to surface tension and buoyancy. Without a counteractive pull from the other unmelted side, lightweight components will rise into the air. Videos of this phenomenon are available to view on public channels such as youtube. 

Question though: which side heats up quicker - the side with wider copper or the side with less copper? Remember the heat energy comes from the atmosphere.

Do you have any thoughts on the through-hole discussion? Any insights would be very welcome. One point we would like to mention is the assembly technique known as "intrusive reflow", Some manufacturing engineers also name it "pin in paste". 

Example of thermal balancing of smd pins with no thermal reliefs (full contact with copper planes)