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7.CAUTIONS

The LEDs are devices which are materialized by combining Blue LEDs and special phosphors.

Consequently, the color of the LEDs is changed a little by an operating current.

Care should be taken after due consideration when using LEDs.

(1) Lead Forming

· When forming leads, the leads should be bent at a point at least 3mm from the base of the epoxy bulb.

Do not use the base of the leadframe as a fulcrum during lead forming.

· Lead forming should be done before soldering.

· Do not apply any bending stress to the base of the lead. The stress to the base may damage the LED’s

characteristics or it may break the LEDs.

· When mounting the LEDs onto a printed circuit board, the holes on the circuit board should be

exactly aligned with the leads of the LEDs. If the LEDs are mounted with stress at the leads,

it causes deterioration of the epoxy resin and this will degrade the LEDs.

(2) Storage

· The LEDs should be stored at 30°C or less and 70%RH or less after being shipped from Nichia and

the storage life limits are 3 months.

If the LEDs are stored for 3 months or more, they can be

stored for a year in a sealed container with a nitrogen atmosphere and moisture absorbent material.

· Nichia LED leadframes are silver plated copper alloy. The silver surface may be affected by

environments which contain corrosive substances. Please avoid conditions which may cause the LED

to corrode, tarnish or discolor. This corrosion or discoloration may cause difficulty during soldering

operations. It is recommended that the LEDs be used as soon as possible.

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

condensation can occur.

(3) Recommended circuit

· In designing a circuit, the current through each LED must not exceed the absolute maximum rating

specified for each LED. It is recommended to use Circuit B which regulates the current flowing

through each LED. In the meanwhile, when driving LEDs with a constant voltage in Circuit A, the

worst case, some LED may be subjected to stresses in excess of the absolute maximum rating.

· This product should be operated in forward bias. A driving circuit must be designed so that the product

is not subjected to either forward or reverse voltage while it is off. In particular, if a reverse voltage is

continuously applied to the product, such operation can cause migration resulting in LED damage.

(A)

(B)

Nichia STS-DA1-0353

<Cat.No.081104>