9
Avago Technologies LED conguration
Precautions:
Lead Forming:
• The leads of an LED lamp may be performed or cut to
length prior to insertion and soldering on PC board.
• If lead forming is required before soldering, care must
be taken to avoid any excessive mechanical stress that
induced into the LED package. Otherwise, cut the
leads to applicable length after soldering process at
room temperature. The solder joint formed will absorb
the mechanical stress, due to the lead cutting, from
traveling to the LED chip die attach and wirebond.
• For better control, it is recommended to use proper
tool to precisely form and cut the leads to applicable
length rather than doing it manually.
Soldering condition:
• Care must be taken during PCB assembly and
soldering process to prevent damage to the LED
component.
• The closest manual soldering distance of the soldering
heat source (soldering iron’s tip) to the body is
1.59mm. Soldering the LED closer than 1.59mm might
damage the LED.
• 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 the recommended temperature and
dwell time. Customer is advised to daily check on the
soldering prole to ensure that the soldering prole
is always conforming to recommended soldering
condition.
Note:
1. PCB with dierent size and design (component density) will
have dierent heat mass (heat capacity). This might cause a
change in temperature experienced by the board if same wave
soldering setting is used. So, it is recommended to re-calibrate
the soldering prole again before loading a new type of PCB.
2. Avago Technologies’ high brightness LED are using high
eciency LED die with single wire bond as shown below.
Customer is advised to take extra precaution during wave
soldering to ensure that the maximum wave temperature is
not exceeding 250°C. Over-stressing the LED during soldering
process might cause premature failure to the LED due to
delamination.
Note: Electrical connection between bottom surface of LED die and
the lead frame material through conductive paste of solder.
• If necessary, use xture to hold the LED component
in proper orientation with respect to the PCB during
soldering process.
• At elevated temperature, the LED is more susceptible
to mechanical stress. Therefore, PCB must allowed to
cool down to room temperature prior to handling,
which includes removal of jigs, xtures or pallet.
• Special attention must be given to board fabrication,
solder masking, surface platting and lead holes size
and component orientation to assure the solderability.
• Recommended PC board plated through holes size for
LED component leads.
LED component
lead size Diagonal
Plated through
hole diameter
0.457 x 0.457 mm
(0.018 x 0.018 inch)
0.646 mm
(0.025 inch)
0.976 to 1.078 mm
(0.038 to 0.042 inch)
0.508 x 0.508 mm
(0.020 x 0.020 inch)
0.718 mm
(0.028 inch)
1.049 to 1.150 mm
(0.041 to 0.045 inch)
• Over sizing of plated through hole can lead to twisting
or improper LED placement during auto insertion.
Under sizing plated through hole can lead to
mechanical stress on the epoxy lens during clinching.
Note: Refer to application note AN1027 for more information on
soldering LED components.
