7
Precautions:
Lead Forming:
• The leads of an LED lamp may be preformed or
cut to length prior to insertion and soldering into
PC board.
• If lead forming is required before soldering, care
must be taken to avoid any excessive mechanical
stress induced to LED package. Otherwise, cut the
leads of LED to length after soldering process at
room temperature. The solder joint formed will
absorb the mechanical stress of the lead cutting
from traveling to the LED chip die attach and
wirebond.
• It is recommended that tooling made to precisely
form and cut the leads to length rather than rely
upon hand operation.
Soldering Condition:
• Care must be taken during PCB assembly and
soldering process to prevent damage to LED
component.
• The closest LED is allowed to solder on board is
1.59mm below the body (encapsulant epoxy) for
those parts without standoff.
• Recommended soldering condition:
Wave
Soldering Manual Solder
Dipping
Pre-heat temperature 105 °C Max. −
Preheat time 30 sec Max −
Peak temperature 250 °C Max. 260 °C Max.
Dwell time 3 sec Max. 5 sec Max
• Wave soldering parameter must be set and
maintain according to recommended temperature
and dwell time in the solder wave. Customer is
advised to periodically check on the soldering
profile to ensure the soldering profile used is
always conforming to recommended soldering
condition.
• If necessary, use fixture to hold the LED
component in proper orientation with respect to
the PCB during soldering process.
• Proper handling is imperative to avoid excessive
thermal stresses to LED components when heated.
Therefore, the soldered PCB must be allowed to
cool to room temperature, 25°C before handling.
• Special attention must be given to board
fabrication, solder masking, surface plating and
lead holes size and component orientation to
assure solderability.
• Recommended PC board plated through holes
Note: Refer to application note AN1027 for more
information on sold eri n g LED components.
LED component
ead size Diagonal Plated through hole
diameter
0.457 x 0.457mm
(0.018 x 0.018inch) 0.646 mm
(0.025 inch) 0.976 to 1.078 mm
(0.038 to 0.042 inch)
0.508 x 0.508mm
(0.020 x 0.020inch) 0.718 mm
(0.028 inch) 1.049 to 1.150mm
(0.041 to 0.045 inch)
Recommended Wave Soldering Profile
BOTTOM SIDE
OF PC BOARD
TOP SIDE OF
PC BOARD
NOTE: ALLOW FOR BOARDS TO BE
SUFFICIENTLY COOLED BEFORE
EXERTING MECHANICAL FORCE.
CONVEYOR SPEED = 1.83 M/MIN (6 FT/MIN)
PREHEAT SETTING = 150 C (100 C PCB)
SOLDER WAVE TEMPERATURE = 245 C
AIR KNIFE AIR TEMPERATURE = 390 C
AIR KNIFE DISTANCE = 1.91 mm (0.25 IN.)
AIR KNIFE ANGLE = 40
SOLDER: SN63; FLUX: RMA
250
200
150
FLUXING
TURBULENT WAVE
PREHEAT
TIME - SECONDS
TEMPERATURE - ˚C
100
50
30
0 10 20 30 40 50 60 70 80 90 100
LAMINAR WAVE
HOT AIR KNIFE