Thermal Pad

Thermal pads in a large, green area, copper surface Thermal pads on a real circuit board

Thermal pads or heat traps are termed solder pads of electronic components, which are not connected to the entire surface of the copper but only with thin webs.

The shrinking of the cross-section prevents the heat from reaching the copper surface, which is electrically connected to the soldering surfaces, such as hand soldering, For example, a masselage, and the soldering process is thereby impaired. In the case of large-area heating of the printed circuit board, for example in the case of mechanical soldering, such as reflow soldering, where the entire printed circuit board is uniformly heated, no thermal pads are necessary but do not interfere as a rule. For small components (design smaller than 1206), heat traps can prevent erecting the components during the solidification phase (gravestone effect / tombstoning) if one component terminal is mounted on a small soldering surface and the other is located in a large soldering surface

Thermal pads are a hindrance to increased requirements for low heat transfer resistances in the field of power electronics, where thermal losses are also dissipated into the metal surfaces via the soldering points. Heat traps also have a negative effect on thermally optimized printed circuit boards with a core made of aluminum, such as are used, for example, as carriers for LED headlights Edit sourcetext

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