NHSW157B Nichia, NHSW157B Datasheet - Page 18

• Manufacturer Part Number: NHSW157B
• Manufacturer: Nichia

Specifications of NHSW157B

• Size Lxwxh (mm): 3.0x1.4x0.52
• Lumi-nous Inten-sity Typ(cd): 3
• Lumi-nous Flux Typ(lm)): 8.8
• Forward Voltage Vf(v) Typ: 3.00
• Forward Voltage Vf(v) Max: 3.30
• Directivity (degree): 120
• If (ma): 20
• Mounting Style: Through Hole

(4) Design Consideration
(5) Electrostatic Discharge (ESD)
(6) Thermal Management
(7) Cleaning
● PCB warpage after mounting the products onto a PCB can cause the package to break.
● The position and orientation of the LEDs affect how much mechanical stress is exerted on the LEDs placed near the score lines.
● Board separation must be performed using special jigs, not using hands.
● The products are sensitive to static electricity or surge voltage. ESD can damage a die and its reliability.
● Proper grounding is required for all devices, equipment, and machinery used in product assembly.
● If tools or equipment contain insulating materials such as glass or plastic,
● The customer is advised to check if the LEDs are damaged by ESD
● ESD damaged LEDs may have current flow at a low voltage or no longer illuminate at a low current.
● Proper thermal management is an important when designing products with LEDs. LED die temperature is affected
● Drive current should be determined for the surrounding ambient temperature (T
● The following equations can be used to calculate the junction temperature of the products.
● If required, isopropyl alcohol (IPA) should be used. Other solvents may cause premature failure to the LEDs
● Ultrasonic cleaning is not recommended since it may have adverse effects on the LEDs
The LED should be placed in a way to minimize the stress on the LEDs due to PCB bow and twist.
The LED should be placed in a way to minimize the stress on the LEDs due to board flexing.
When handling the products, the following measures against electrostatic discharge are strongly recommended:
Surge protection should be considered when designing of commercial products.
the following measures against electrostatic discharge are strongly recommended:
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).
by PCB thermal resistance and LED spacing on the board. Please design products in a way that the LED die temperature
does not exceed the maximum Junction Temperature (T
1) T
due to the damage to the resin portion. The effects of such solvents should be verified prior to use.
In addition, the use of CFCs such as Freon is heavily regulated.
depending on the ultrasonic power and how LED is assembled.
If ultrasonic cleaning must be used, the customer is advised to make sure the LEDs will not be damaged prior to cleaning.
Eliminating the charge
Grounded wriststrap, ESD footwear, clothes, and floors
Grounded workstation equipment and tools
ESD table/shelf mat made of conductive materials
Dissipating static charge with conductive materials
Preventing charge generation with moisture
Neutralizing the charge with ionizers
Failure Criteria: V
*T
T
T
R
R
W=Input power(I
J
=T
A
S
θJA
θJS
J
=LED junction temperature: °C
=Ambient temperature: °C
=Soldering temperature (cathode side): °C
A
=Thermal resistance from junction to ambient: °C/W
=Thermal resistance from junction to T
+R
Ts Point
θJA
･W
F
<2.0V at I
F
×V
2) T
F
): W
J
=T
F
S
=0.5mA
+R
θJS
･W
S
measuring point: °C/W
J
).
A
) to dissipate the heat from the product.
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