RF-BU1608TS-DC-E0 Blue LED Datasheet - Size 1.6x0.8x0.55mm - Voltage 2.8-3.5V - Power 105mW

1. Product Overview

1.1 General Description

The RF-BU1608TS-DC-E0 is a color LED fabricated using a blue chip. It comes in a compact 1.6mm x 0.8mm x 0.55mm surface-mount package, making it suitable for space-constrained applications. This LED offers a wide viewing angle of 120 degrees and is designed for all SMT assembly and solder processes. It is RoHS compliant and has a moisture sensitivity level of 3.

1.2 Features

• Extremely wide viewing angle (120°)
• Suitable for all SMT assembly and solder processes
• Moisture sensitivity level: Level 3
• RoHS compliant

1.3 Applications

• Optical indicators
• Switches and symbol displays
• General purpose indication

2. Package Dimensions and Polarity

2.1 Mechanical Drawing

The LED package measures 1.6mm (length) x 0.8mm (width) x 0.55mm (height). Tolerances are ±0.2mm unless otherwise noted. All dimensions are in millimeters. The top view shows the LED position, and the bottom view indicates the polarity. There are two pads: pad 1 is the anode and pad 2 is the cathode.

2.2 Soldering Patterns

The recommended soldering pattern (footprint) is provided in the datasheet. It is designed for optimal thermal and mechanical performance. The pattern dimensions are based on the package footprint.

3. Technical Parameters

3.1 Electrical and Optical Characteristics (Ts=25°C)

Key electrical and optical parameters at IF=20mA:

Measurement tolerances: Forward voltage ±0.1V, dominant wavelength ±2nm, luminous intensity ±10%.

3.2 Absolute Maximum Ratings (Ts=25°C)

Care must be taken not to exceed these ratings. The maximum current should be determined after measuring the package temperature to ensure the junction temperature does not exceed 95°C.

3.3 Thermal Characteristics

The thermal resistance from junction to solder point (RTHJ-S) is 450°C/W typical. This indicates that for every 20mA of forward current, the temperature rise will be moderate. Proper thermal management is essential to maintain LED performance and lifespan.

4. Binning System

4.1 Forward Voltage Bins

Forward voltage is binned into seven groups: G1 (2.8-2.9V), G2 (2.9-3.0V), H1 (3.0-3.1V), H2 (3.1-3.2V), I1 (3.2-3.3V), I2 (3.3-3.4V), J1 (3.4-3.5V). This allows for tighter circuit design and consistent brightness in applications.

4.2 Wavelength Bins

Dominant wavelength is sorted into four bins: C00 (460-465nm), D00 (465-470nm), E00 (470-475nm), F00 (475-480nm). These cover the blue region from deep blue to slightly greenish blue.

4.3 Luminous Intensity Bins

Luminous intensity is divided into five bins: H00 (150-230mcd), I00 (230-350mcd), J00 (350-530mcd), K00 (530-800mcd), L00 (800-1200mcd). This wide range enables selection for different indicator brightness requirements.

5. Optical Characteristics Curves

5.1 Forward Voltage vs Forward Current

The typical I-V curve shows a forward voltage of approximately 2.8V at 5mA, rising to about 3.2V at 25mA. The curve follows the standard diode exponential relationship.

5.2 Forward Current vs Relative Intensity

Relative intensity increases almost linearly with forward current up to 30mA. At 20mA the relative intensity is about 1.0 (normalized), and at 10mA it is about 0.5.

5.3 Temperature Effects

As ambient temperature rises from 0°C to 100°C, the relative intensity decreases by approximately 30%. Similarly, the maximum allowed forward current derates with increasing pin temperature. At 100°C, the forward current must be reduced to about 10mA to avoid overheating.

5.4 Spectral Distribution

The spectral distribution at 20mA and 25°C shows a peak around 470nm with a half bandwidth of 15nm. The spectrum is narrow, confirming a saturated blue color.

5.5 Radiation Pattern

The radiation pattern is nearly Lambertian with a wide half-angle of 120 degrees. The relative luminous intensity remains above 50% up to ±60 degrees off axis.

6. Packaging Information

6.1 Carrier Tape and Reel

The LEDs are packaged in carrier tape with a width of 8.0±0.1mm. The reel dimensions are: outer diameter 178±1mm, inner hub diameter 60±1mm, and spindle hole diameter 13.0±0.5mm. Each reel contains 4000 pieces.

6.2 Label Specification

The reel label includes part number, spec number, lot number, bin code for luminous intensity, chromaticity bin (XY), forward voltage bin, wavelength code (WLD), quantity, and date of manufacture.

6.3 Moisture Resistant Packaging

The LEDs are shipped in moisture barrier bags (MBB) with desiccant. The bag is vacuum sealed to maintain a low humidity environment. A humidity indicator card may be included. The MSL level is 3, meaning floor life is 168 hours after opening the bag, provided ambient conditions are below 30°C and 60% RH.

7. Reliability Testing

7.1 Test Items and Conditions

Reliability tests include: Reflow soldering (260°C max, 10 sec, 2 times), Temperature cycling (-40°C to 100°C, 100 cycles), Thermal shock (-40°C to 100°C, 300 cycles), High temperature storage (100°C, 1000 hours), Low temperature storage (-40°C, 1000 hours), and Life test (25°C, IF=20mA, 1000 hours). All tests are performed on 22 pieces with acceptance criteria of 0/1.

7.2 Failure Criteria

Failures are defined as: Forward voltage increase beyond 1.1 times upper spec limit, reverse current exceeding 2.0 times upper spec limit (at VR=5V), and luminous flux dropping below 0.7 times lower spec limit.

8. SMT Reflow Soldering

8.1 Reflow Profile

The recommended reflow profile has the following parameters: Preheating from 150°C to 200°C for 60-120 seconds, ramp-up rate ≤3°C/s, time above 217°C (TL) for 60-150 seconds, peak temperature (TP) 260°C with a maximum time within 5°C of peak of 30 seconds (actual tp max 10 seconds), and cooling rate ≤6°C/s. Total time from 25°C to peak should not exceed 8 minutes. Reflow should not be performed more than twice.

8.2 Hand Soldering and Repair

If hand soldering is necessary, use a soldering iron at ≤300°C for less than 3 seconds, and only one time. Repair after reflow is discouraged; if unavoidable, use a double-head soldering iron and verify LED characteristics.

8.3 Precautions

Do not mount LEDs on warped PCB portions. Avoid mechanical stress or vibration during cooling. Do not rapidly cool after soldering. Ensure the PCB is clean and flat.

9. Handling and Storage Precautions

9.1 Environmental Considerations

The sulfur content in the operating environment and mating materials should not exceed 100PPM. Halogen content: Bromine <900PPM, Chlorine <900PPM, total Bromine+Chlorine <1500PPM. Avoid volatile organic compounds (VOCs) that can penetrate the silicone encapsulant and cause discoloration.

9.2 Circuit Design Notes

Always include a current-limiting resistor to prevent current surge. Ensure the reverse voltage is not applied, as it can cause migration and LED damage. The forward voltage should only be applied when the circuit is on or off.

9.3 Storage Conditions

Before opening the aluminum bag: Store at ≤30°C and ≤75% RH for up to 1 year from date of manufacture. After opening: Use within 168 hours if stored at ≤30°C and ≤60% RH. If these conditions are exceeded, bake the LEDs at 60±5°C for ≥24 hours.

9.4 ESD Protection

LEDs are sensitive to electrostatic discharge (ESD) and electrical overstress (EOS). Follow standard ESD precautions: use grounded workstations, antistatic wrist straps, and conductive packaging.

10. Application Notes

10.1 Typical Use Cases

This blue LED is ideal for status indicators, backlighting for switches and symbols, and general purpose indication in consumer electronics, automotive interiors, and industrial controls.

10.2 Design Considerations

When designing the circuit, consider the forward voltage bin to ensure consistent brightness. The wide viewing angle (120°) allows placement at various angles. For high ambient temperature applications, derating of forward current is necessary. Use a minimum of 1oz copper on the PCB for adequate heat dissipation.

11. Frequently Asked Questions

11.1 What is the typical forward voltage?

The forward voltage ranges from 2.8V to 3.5V depending on the bin. At 20mA, typical values fall in the 3.0-3.2V range for most bins.

11.2 How to handle moisture sensitivity?

This LED has MSL Level 3. After opening the moisture barrier bag, the floor life is 168 hours at ≤30°C/≤60%RH. If not used within this time, bake at 60°C for 24 hours before reflow.

11.3 Can I use this LED in outdoor applications?

It can be used in indoor or outdoor applications as long as the operating temperature range (-40°C to +85°C) is maintained. However, direct exposure to sunlight may reduce contrast. Ensure proper encapsulation if exposed to harsh environments.

12. Principle of Operation

This LED uses a blue gallium nitride (GaN) based chip that emits light when forward biased. The chip is encapsulated in a clear epoxy or silicone package with a defined optical lens shape to achieve the 120° viewing angle. No phosphor conversion is used; the emission is direct blue light at the chip wavelength.

13. Development Trends

The trend in SMD LEDs is towards even smaller packages (such as 0402) and higher luminous efficacy. This 0603 size LED offers a good balance between size and light output. Advances in chip technology continue to increase efficiency and brightness while maintaining reliability. The use of blue LEDs in indicator applications remains strong due to their high visibility and low power consumption.