NICHIA STS-DA1-3555F <Cat.No.180925>

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(3) Handling Precautions

● Do not handle the LEDs with bare hands as it will contaminate the LED surface and may affect the optical characteristics: it might

cause the LED to be deformed and/or the bump to break, which will cause 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 internal connection to fail 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 internal connection to fail causing a catastrophic failure (i.e. the LED not to illuminate).

(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.

● If an aluminum-core PCB is used to operate the LEDs, it may cause thermal stress during operation causing damage to the solder

joints (e.g. crack). Ensure that sufficient verification is performed prior to use.

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

secondary lens, lens cover, etc.) may penetrate LED lens and/or internal pre-coating 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 cause a 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.

(5) Electrostatic Discharge (ESD)

● This LED is sensitive to transient excessive voltages (e.g. ESD, lightning surge). If this excessive voltage occurs in the circuit, it

may cause the LED to be damaged causing issues (e.g. the LED to become dimmer or not to illuminate [i.e. catastrophic failure]).

Ensure that when handling the LEDs, necessary measures are taken to protect them from an ESD discharge. The following

examples are recommended measures to eliminate the charge:

- Grounded wrist strap, ESD footwear, clothes, and floors

- Grounded workstation equipment and tools

- ESD table/shelf mat made of conductive materials

● Ensure that all necessary measures are taken to prevent the LEDs from being exposed to transient excessive voltages (e.g. ESD,

lightning surge):

- tools, jigs, and machines that are used are properly grounded

- appropriate ESD materials/equipment are used in the work area

- the system/assembly is designed to provide ESD protection for the LEDs

● If the tool/equipment used is an insulator (e.g. glass cover, plastic, etc.), ensure that necessary measures have been taken to

protect the LED from transient excessive voltages (e.g. ESD). The following examples are recommended measures to eliminate

the charge:

- Dissipating static charge with conductive materials

- Preventing charge generation with moisture

- Neutralizing the charge with ionizers

● To detect if an LED was damaged by transient excess voltages (i.e. an ESD event during the system’s assembly process), perform

a characteristics inspection (e.g. forward voltage measurement, light-up test) at low curren

t (≤1mA).

● Failure Criteria: V

If the LED is damaged by transient excess voltages (e.g. ESD), it will cause:

- the LED not to illuminate at a low current