NICHIA STS-DA1-5625 <Cat.No.190328>

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(2) Directions for Use

● The circuit must be designed to ensure that the Absolute Maximum Ratings are not exceeded for each LED. The LEDs should be

operated at a constant current per LED. In the case of operating at a constant voltage, Circuit B is recommended. If Circuit A is

used, it may cause the currents flowing through the LEDs to vary due to the variation in the forward voltage characteristics of the

LEDs on the circuit.

(A)

(B)

● This LED is designed to be operated at a forward current. Ensure that no voltage is applied to the LED in the forward/reverse

direction while the LED is off. If the LEDs are used in an environment where reverse voltages are applied to the LED continuously,

it may cause electrochemical migration to occur causing the LED to be damaged. When not in use for a long period of time, the

system’s power should be turned off to ensure that there are no issues/damage.

● To stabilize the LED characteristics while in use, Nichia recommends that the LEDs are operated at currents ≥ 10% of the sorting

current.

● Ensure that transient excessive voltages (e.g. lighting surge) are not applied to the LEDs.

● If a secondary lens is used to collimate or diffuse the light, sufficient verification should be performed prior to use to ensure that

there are no issues (e.g. color variation).

● If the LEDs are used for outdoor applications, ensure that necessary measures are taken (e.g. protecting the LEDs from water/salt

damage and high humidity).

(3) Handling Precautions

● Do not handle the LEDs with bare hands:

- this may contaminate the LED surface and have an effect on the optical characteristics,

- this may cause the LED to deform and/or the wire to break causing a catastrophic failure (i.e. the LED not to illuminate).

● Ensure that when handling the LEDs with tweezers, excessive force is not applied to the LED. Otherwise, it may cause damage to

the resin (e.g. cut, scratch, chip, crack, delamination and deformation) and the wire to break causing a catastrophic failure (i.e.

the LED not to illuminate).

● Dropping may cause damage to the LED (e.g. deformation).

● Do not stack assembled PCBs together. Otherwise, it may cause damage to the resin (e.g. cut, scratch, chip, crack, delamination

and deformation) and the wire to break causing a catastrophic failure (i.e. the LED not to illuminate).

● CRI Rank R9050 LEDs in this specification use materials that contain halogen-based compounds; the halogen element found in

these materials will not affect the LEDs when the LEDs are used under the conditions detailed in this specification. The other CRI

ranks in this specification do not use these materials.

● Due to the variation in the amount of the reflective material (white resin) that is coating the protection device, the area around

the protection device may appear to be a black spot; this will not affect the characteristics of the LED. Do not use the location of

the protection device to determine the polarity of the LED; use the cathode mark.

(4) Design Consideration

● If the LEDs are soldered to a PCB and the PCB assembly is bent (e.g. PCB depaneling process), it may cause the LED package to

break. The PCB layout should be designed to minimize the mechanical stress on the LEDs when the PCB assembly is bent/warped.

● The amount of mechanical stress exerted on the LED from depaneling may vary depending on the LED position/orientation on the

PCB assembly (e.g. especially in areas near V-groove scores). The PCB layout should be designed to minimize the mechanical

stress on the LEDs when the PCB is separated into individual PCB assemblies.

● To separate a PCB populated with the LEDs, use a specially designed tool. Do not break the PCB by hand.

● Volatile organic compounds that have been released from materials present around the LEDs (e.g. housing, gasket/seal, adhesive,

secondary lens, lens cover, etc.) may penetrate the LED lens and/or encapsulating resin. If the LEDs are being used in a

hermetically sealed environment, these volatile compounds can discolor after being exposed to heat and/or photon energy and

it may greatly reduce the LED light output and/or color shift. In this case, ventilating the environment may improve the reduction

in light output and/or color shift. Perform a light-up test of the chosen application for optical evaluation to ensure that there are

no issues, especially if the LEDs are planned to be used in a hermetically sealed environment.