Light Emitting Diode
This document contains tentative information, Nichia may change the contents without notice.
12/14
SP-QR-C2-220184-1
Jun. 8, 2022
Assembly Precautions for the Nichia 193F Series LEDs
Figure 8. Example of Reference Point to Detect, Recognize, or Locate
the Electrodes/Die Heatsink
1. The nozzle should further press the LED 0.2mm onto the PCB from the
height where the LED first touches solder paste.
If the release point of the nozzle is too high,
- it may cause placement issues (e.g. the LED to stick to the nozzle
after placement, the LED to be mounted in an incorrect
place/rotated position, the LED to become soldered to the PCB in
a tilted position, etc.).
If the release point of the nozzle is too low,
- excessive forces may be applied to the LED during placement and
it may cause the LED to become damaged.
1. Nichia recommends using the electrodes and die heatsink as a reference
to locate the center of the LED.
2. If the imaging device has trouble detecting/recognizing the
electrodes/die heatsink, adjust the settings (i.e. the brightness of the
light, etc.) of the pick-and-place machine.
3. If an automatic polarity detector is used for the LEDs, set up the imaging
device to detect the empty space between the die heatsink and
electrodes (i.e. Polarity Detection/Recognition Point in Figure 8 to the
left). In the example in Figure 8, the equipment measures the brightness
of the empty space against the threshold to locate the electrodes
and/or determine the polarity.
Placement
Depth
0.2mm
Pick-and-Place Nozzle
PCB
LED
0.9mm
4.4 Recommended Nozzle Height for Placement Operations (Placement Depth)
Figure 7. Recommended Nozzle Height for Placement (Placement Depth)
4.5 Imaging-based Automatic Inspection
Electrode/Die Heatsink Location
Detection/Recognition Points
Polarity Detection/Recognition
Point
