8/15

(Ver 1.0)

9. Cautions

The LEDs are device which are materialized by combining Blue LEDs and special phosphors. Consequently,

the color of White LEDs is subject to change a little by an operating current.

Care should be taken after due consideration when using LEDs.

(1) Moisture-Proof Package

• When moisture is absorbed into the SMT package it may vaporize and expand products during soldering.

There is a possibility that this may cause exfoliation of the contacts and damage to the optical characteristics

of the LEDs. For this reason, the moisture-proof package is used to keep moisture to a minimum in the

package.

• A package of a moisture-absorbent material (silica gel) is inserted into the shielding bag. The silica gel

changes its color from blue to pink as it absorbs moisture.

(2) Storage

• Storage Conditions

- Before opening the package :

The LEDs should be kept at 5℃~30

or less and

℃

65%RH or less. The LEDs should be used within a year.

When storing the LEDs, moisture-proof packaging with moisture-absorbent material (silica gel) is

recommended.

- After opening the package :

The LEDs should be kept at 5℃~40

or less and

℃

30%RH or less. The LEDs should be soldered within 168

hours (7 days) after opening the package. If unused LEDs remain, they should be stored in moisture-proof

packages, such as sealed containers with packages of moisture-absorbent material (silica gel). It is also

recommended to return the LEDs to the original moisture-proof bag and to reseal the moisture-proof bag

again.

• If the moisture-absorbent material (silica gel) has faded away or the LEDs have exceeded the recommended

storage time, baking treatment should be performed using the following conditions.

- Baking treatment : more than 48 hours at 45±5℃ (Reel condition)

more than 24 hours at 125±5℃ (Each piece condition)

• After assembly and during use, silver plating can be affected by the corrosive gases emitted by components

and materials in close proximity of the LEDs within an end product, and the gases entering into the product

from the external atmosphere. The above should be taken into consideration when designing.

• Please avoid rapid transitions in ambient temperature, especially in high humidity environments where

condensation can occur.

(3) Heat Generation

• Thermal design of the end product is of paramount importance. Please consider the heat generation of the

LED when the system is designed. The coefficient of temperature increase per input electric power is

affected by the thermal resistance of the circuit board and density of LED placement on the board, as well as

other components. It is necessary to avoid intense heat generation and operate within the maximum ratings

given in the specification.

• The operating current should be decided after considering the ambient maximum temperature of LEDs.