The LP8863-Q1 device has a LED string configuration auto-detection feature. Every time powered on, the device automatically detects the number of connected LED strings so as to select the correct phase shift.

This application report firstly introduces the mechanism of LP8863-Q1 string auto-detection, gives the detection flow step by step. Then, it analyzes two common application issues: the first case is using invalid LED string configuration, the second case is powering off then powering on quickly, both could affect the proper string configuration auto-detection, leading to a wrong phase shift and fault misreporting. Lastly the article gives a software method to solve the problem.