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APPLICATION NOTES FOR SMD LEDs
Rev No: V9 1/22/2015 Page 1 www.kingbright.com
Storage conditions
SMD devices are usually moisture/reflow sensitive. Moisture from atmospheric humidity enters permeable
packaging materials by diffusion. Assembly processed used to solder SMD packages to PCBs expose the
entire package body to temperature between 160℃ - 260 . During solder reflow, rapid moisture expansion ℃
can result in package cracking, delamination of critical interfaces within the package, or damaged gold wire.
1. Scope: Application notes listed in this document apply to SMD products include the KA, KP, KM, KPK, and
KT series.
2. Unopened moisture barrier bag (MBB) shall be stored at temperature below 40℃ with humidity below
90%RH.
3. After the MBB has been opened, the LEDs should be used according to the floor life specified in the table
below.
3.1：IPC/JEDEC J-STD-020 Moisture Sensitivity Levels
FLOOR LIFE
LEVEL
TIME CONDITIONS
1 Unlimited
≦30℃/85% RH
2 1 year
≦30℃/60% RH
2a 4 weeks
≦30℃/60% RH
3 168 hours
≦30℃/60% RH
4 72 hours
≦30℃/60% RH
5 48 hours
≦30℃/60% RH
5a 24 hours
≦30℃/60% RH
6 Time on Label(TOL)
≦30℃/60% RH
4. If the Humidity Indicator Card (HIC)’s 10 % mark has changed, or the LEDs have not been used within the
floor life specified, they should be baked with the following conditions to reset the floor life:
Type
Temperature Humidity Bake Time
When still in carrier tape
60±3℃
<5%RH 100H
When out of carrier tape
110℃
/ 10H
* Not more than once
5. Do not store LEDs in an environment where high humidity or acidic/basic chemicals are present, as they
will degrade the LED’s metallic surfaces.
6. LED leadframe and soldering pads (cathode and anode) are plated with gold, tin, or other metals. Under
long-term exposure to open air, the exposed pins and pads may become oxidized causing poor
solderability. Therefore opened but unused parts must be stored in sealed containers. Suggest to store
unused parts in the original moisture barrier bag.
7. Moisture control for components already mounted on PCB：If the PCB will not undergo additional reflow
soldering or high-temperature processes, then no special treatment is required for the mounted
moisture-sensitive SMD components. If the PCB will undergo multiple reflow soldering or other
