Hi Jürgen,
Der Layouter hätte mal ins Datenblatt sehen sollen... Bei einem
Linearregler war das aber abzusehen:
"It is very important to use a good thermal PCB board layout to maximize
charging current. The thermal path for the heat generated by the IC is
from the die to the copper lead frame through the package lead
(especially the ground lead) to the PCB board copper, the PCB board
copper is the heat sink. The footprint copper pads should be as wide as
possible and expand out to larger copper areas to spread and dissipate
the heat to the surrounding ambient. Feedthrough vias to inner or
backside copper layers are also useful in improving the overall thermal
performance of the charger."
Wer lesen kann, ist klar im Vorteil.
Also setze auf die Unterseite eine kräftige Wärmesenke, dann gehts besser.
Marte