If the IC becomes excessively hot immediately after power-up, it usually indicates an internal short or a short in the display panel's COF (Chip-on-Film).
Since appears to be a typo or a partial reference, this detailed review covers the most likely component you are looking for: the 1N5189 (a standard Silicon Switching Diode often referenced in lists near "518") or the general 1N518x series . Inx In518 Ic Pinout Diagram
: Current sense pin to monitor the current flowing through the LEDs. Visual Reference Examples If the IC becomes excessively hot immediately after