NICHIA STS-DA1-1379A <Cat.No.110629>

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(4) Design Consideration

● PCB warpage after mounting the products onto a PCB can cause the package to break.

The LED should be placed in a way to minimize the stress on the LEDs due to PCB bow and twist.

● The position and orientation of the LEDs affect how much mechanical stress is exerted on the LEDs placed near the score lines.

The LED should be placed in a way to minimize the stress on the LEDs due to board flexing.

● Board separation must be performed using special jigs, not using hands.

● If an aluminum PCB is used, customer is advised to verity the PCB with the products before use.

Thermal stress during use can cause the solder joints to crack.

(5) Electrostatic Discharge (ESD)

● The products are sensitive to static electricity or surge voltage. ESD can damage a die and its reliability.

When handling the products, the following measures against electrostatic discharge are strongly recommended:

Eliminating the charge

Grounded wriststrap, ESD footwear, clothes, and floors

Grounded workstation equipment and tools

ESD table/shelf mat made of conductive materials

● Proper grounding is required for all devices, equipment, and machinery used in product assembly.

Surge protection should be considered when designing of commercial products.

● If tools or equipment contain insulating materials such as glass or plastic,

the following measures against electrostatic discharge are strongly recommended:

Dissipating static charge with conductive materials

Preventing charge generation with moisture

Neutralizing the charge with ionizers

● The customer is advised to check if the LEDs are damaged by ESD

when performing the characteristics inspection of the LEDs in the application.

Damage can be detected with a forward voltage measurement or a light-up test at low current (≤1mA).

● ESD damaged LEDs may have current flow at a low voltage or no longer illuminate at a low current.

(6) Thermal Management

● Proper thermal management is an important when designing products with LEDs. LED die temperature is affected

by PCB thermal resistance and LED spacing on the board. Please design products in a way that the LED die temperature

● The following equations can be used to calculate the junction temperature of the products.

Ts Point