With the increasing improvement of process and equipment accuracy of major packaging plants, the chip size of Mini LED applications has gradually evolved from 5x9mil to today's 3x5mil, even smaller. The reduction of chip size means that more LED chips can be arranged in the same unit area of display  or backlight unit, and higher requirements are put forward for chip mounting. At the same time, higher requirements are put forward for chip mounting.   First of all, the most significant change is that the pad size of the PCB becomes smaller, and the correspondin...