NICHIA STS-DA1-1304B <Cat.No.110331>

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(4) Design Consideration

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

The LEDs should be placed so as 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 LEDs should be placed so as to minimize the stress on the LEDs due to board flexing.

● Board separation must be performed using special jigs, not with 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. An ESD event may damage its die

or reduce its reliability performance. When handling the products, measures against electro static discharge,

including the followings, are strongly recommended.

Eliminating the charge;

Wrist strap, ESD footwear and garments, ESD floors

Grounding the equipment and tools at workstation

ESD table/shelf mat (conductive materials)

● Proper grounding techniques are required for all devices, equipment and machinery used in the assembly of the products.

Also note that surge protection should be considered in the design of customer products.

● If tools or equipment contain insulating materials, such as glass or plastic, proper measures against electro static discharge,

including the followings, are strongly recommended.

Dissipating the charge with conductive materials

Preventing the charge generation with moisture

Neutralizing the charge with ionizers

● When performing the characteristics inspection of the LEDs in your application, customer is advised to check on the LEDs

whether or not they are damaged by ESD. Such damage can be detected during forward voltage measurement or light up test

at low current. (the recommended current is 1mA or lower)

● ESD-damaged LEDs may have a current flow at low voltage, or no longer light up at low current.

(6) Thermal Management

● Thermal management is an important factor when designing your product by using the LEDs.

The rise in LED die temperature can be affected by PCB thermal resistance or/and LED spacing as mounted on the board.

Customer is advised to design the product to ensure that the LED die temperature

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

Ts Point