RF-OMRB14TS-AK Red LED PLCC2 - Size 2.2x1.4x1.3mm - Voltage 1.8V - Power 72mW - Automotive Grade

1. Product Overview

The RF-OMRB14TS-AK is a high-performance red Surface-Mount Device (SMD) LED in a PLCC-2 package, designed for demanding automotive interior lighting applications. This component utilizes advanced AlGaInP (Aluminum Gallium Indium Phosphide) epitaxial technology on a substrate, delivering rich red emission with a dominant wavelength centered around 615 nm. The package dimensions are 2.2 mm × 1.4 mm × 1.3 mm (length × width × height), making it suitable for compact PCB designs. The LED features an extremely wide viewing angle of 120 degrees, ensuring uniform light distribution. It is qualified according to AEC-Q101 stress test standards for automotive-grade discrete semiconductors, guaranteeing reliability under harsh conditions. The moisture sensitivity level is Class 2, and the device is fully RoHS and REACH compliant.

2. Technical Parameter Interpretation

2.1 Electrical Characteristics

The forward voltage (V_F) at a test current of 20 mA has a minimum of 1.8 V, typical of 2.0 V, and a maximum of 2.4 V. This relatively low forward voltage is characteristic of AlGaInP red LEDs. The reverse current (I_R) at a reverse voltage of 5 V is less than 10 µA, indicating excellent rectifying behavior. The maximum allowed forward current is 30 mA DC, with a peak forward current of 100 mA at a 1/10 duty cycle and 10 ms pulse width. The total power dissipation is limited to 72 mW, which must be respected to avoid thermal damage.

2.2 Optical Characteristics

At 20 mA, the typical luminous intensity (I_V) is 800 mcd, with a minimum of 800 mcd and a maximum of 1200 mcd per the L2 bin. The dominant wavelength (λ_D) ranges from 612.5 nm to 620 nm, with a typical value of 615 nm, placing the emission in the deep red region. The viewing angle (2θ_1/2) is 120 degrees, providing a wide radiation pattern suitable for interior ambient lighting.

2.3 Thermal Characteristics

The thermal resistance from junction to solder point (R_thJ-S) is specified as 300 °C/W (max). This parameter is critical for thermal management. The junction temperature (T_J) must not exceed 120 °C, and the operating temperature range is -40 °C to +100 °C. Proper heat sinking is essential to maintain the LED within safe limits.

3. Binning System Explanation

3.1 Forward Voltage Bins

The forward voltage is binned into six groups: B1 (1.8–1.9 V), B2 (1.9–2.0 V), C1 (2.0–2.1 V), C2 (2.1–2.2 V), D1 (2.2–2.3 V), D2 (2.3–2.4 V). This allows customers to select LEDs with closely matched V_F for parallel string designs.

3.2 Luminous Intensity Bins

Two intensity bins are defined: L1 (800–1000 mcd) and L2 (1000–1200 mcd). The specified typical value (800 mcd) corresponds to the lower end of L1, but production can ship either bin depending on the order.

3.3 Wavelength Bins

Dominant wavelength is divided into three bins: C2 (612.5–615.0 nm), D1 (615.0–617.5 nm), D2 (617.5–620.0 nm). The typical wavelength of 615 nm falls in the D1 bin. The tight binning ensures color consistency in multi-LED modules.

4. Performance Curve Analysis

4.1 Forward Voltage vs. Forward Current

Figure 1-6 shows an almost linear relationship: as forward current increases from 0 to 30 mA, forward voltage rises from about 1.7 V to 2.3 V. This is typical for AlGaInP LEDs and designers must account for the V_F variation when using constant-voltage drive.

4.2 Relative Intensity vs. Forward Current

Figure 1-7 demonstrates that relative luminous intensity increases with current. At 20 mA the intensity is normalized; doubling the current to 40 mA would roughly double the output (though the absolute maximum current is 30 mA DC).

4.3 Temperature Dependence

Figure 1-8 shows that relative luminous flux decreases as solder temperature (T_S) rises. At 100 °C, the output can drop to about 70% of the value at 25 °C. Figure 1-9 indicates that maximum allowed forward current must be derated above 55 °C to avoid exceeding the 120 °C junction temperature limit. Figure 1-10 confirms that forward voltage decreases with temperature at a rate of approximately -2 mV/°C.

4.4 Radiation Diagram

Figure 1-11 shows a Lambertian-like radiation pattern with a half-angle of ±60° from the optical axis. The relative intensity remains above 50% up to ±60°, confirming the wide viewing angle claim.

4.5 Wavelength vs. Current

Figure 1-12 indicates a slight red-shift of the dominant wavelength with increasing current: from about 614 nm at 5 mA to 618 nm at 30 mA. The effect is minor but should be considered if precise color matching is required.

4.6 Spectrum Distribution

Figure 1-13 provides the normalized spectral power distribution. The emission peaks near 630 nm with a full-width at half-maximum (FWHM) of approximately 20 nm. No secondary peaks are present, confirming good color purity.

5. Mechanical and Packaging Information

5.1 Package Dimensions

The top-view dimensions are 2.2 mm × 1.4 mm; the height is 1.3 mm. The anode is indicated by a dot on the package (Figure 1-4). The recommended soldering pad layout (Figure 1-5) uses two rectangular pads: 0.8 mm × 1.2 mm each with a 1.4 mm spacing. All tolerances are ±0.20 mm unless noted.

5.2 Carrier Tape and Reel

The LED is packaged in 8 mm carrier tape with 3000 pieces per reel. Key tape dimensions: pocket pitch P0 = 4.0 mm, component pitch P1 = 4.0 mm, sprocket hole pitch P2 = 2.0 mm, tape width W = 8.0 mm. Reel outer diameter is 178 mm, hub diameter 60 mm.

5.3 Label and Moisture Barrier

Each reel carries a label showing part number, spec number, lot number, bin code (VF bin, intensity bin, wavelength bin), quantity, and date code. Reels are vacuum-sealed in a moisture barrier bag with desiccant and a humidity indicator card, meeting MSL-2 requirements.

6. Soldering and Assembly Guide

6.1 Reflow Soldering Profile

The recommended reflow profile follows JEDEC J-STD-020. Key parameters: ramp-up rate ≤ 3 °C/s, preheat from 150 °C to 200 °C for 60–120 s, time above 217 °C (T_L) of 60–150 s, peak temperature (T_P) 260 °C for max 10 s within 5 °C of T_P, and cool-down rate ≤ 6 °C/s. Only two reflow cycles are allowed. If the time between two soldering steps exceeds 24 hours, the LEDs may be damaged.

6.2 Hand Soldering and Repair

If hand soldering is necessary, use a soldering iron tip temperature below 300 °C and keep contact time under 3 seconds, and only one rework is permitted. For repair, a double-head soldering iron is recommended; avoid touching the silicone lens with the iron.

6.3 Storage Conditions

Before opening the sealed bag, store at ≤30 °C and ≤75% RH for up to one year from the date of sealing. After opening, the LEDs should be used within 24 hours at ≤30 °C and ≤60% RH. If the humidity indicator card shows excessive moisture or the storage time is exceeded, bake the components at 60±5 °C for at least 24 hours before use.

7. Packaging and Ordering Information

The standard packaging quantity is 3000 pieces per reel. Each reel is placed in a moisture barrier bag with a label. The label includes the part number (e.g., RF-OMRB14TS-AK), spec number, lot number, bin code (VF, IV, WLD), quantity, and date. The final shipping carton contains multiple reels. The ordering code should reference the specific bin requirements if precise matching is needed. It is recommended to consult the factory for availability of specific V_F, intensity, and wavelength bins.

8. Application Recommendations

8.1 Typical Applications

The primary application is automotive interior lighting, such as dashboard backlighting, ambient light strips, dome lights, and indicator lamps. The wide viewing angle is beneficial for uniform panel illumination. The AEC-Q101 qualification ensures reliability over vehicle lifetime.

8.2 Design Considerations

• Current Derating: Always operate below 30 mA DC; derate above 55 °C ambient as per Figure 1-9.
• Thermal Management: Use adequate copper pads and thermal vias to keep solder point temperature below 85 °C for maximum light output stability.
• ESD Protection: The LED has an HBM ESD withstand voltage of 2000 V. However, ESD protection is still recommended during handling and assembly. Use grounded workstations and antistatic packaging.
• Circuit Design: To avoid thermal runaway, use a current-limiting resistor per LED or a constant-current driver. Parallel connection of LEDs with different V_F bins can cause uneven current distribution.
• Optical Design: The Lambertian-like radiation pattern allows easy integration into light guides or diffusers. The 120° viewing angle covers a wide area.
• Sulfur and Halogen Control: The environment must keep sulfur content below 100 ppm in mating materials. Bromine and chlorine contents in external materials should each be below 900 ppm, with a total below 1500 ppm, to prevent corrosion of the silver-plated leadframe.

9. Technology Comparison

Compared to conventional red LEDs using GaAsP or GaP technologies, the AlGaInP-based RF-OMRB14TS-AK offers higher luminous efficacy (up to 40 lm/W at 20 mA) and better temperature stability. Its PLCC-2 package provides a smaller footprint than older through-hole parts and is compatible with automated SMT assembly. The 120° viewing angle is wider than many competing red LEDs (often 110° or less), giving more design flexibility for uniform lighting. AEC-Q101 qualification sets it apart from consumer-grade LEDs, making it suitable for safety-critical automotive applications.

10. Frequently Asked Questions

Q: Can I drive this LED at 30 mA continuously?
A: Yes, the absolute maximum forward current is 30 mA DC, but you must ensure the junction temperature stays below 120 °C. At the maximum rated power of 72 mW (30 mA × 2.4 V), the temperature rise is 72 mW × 300 °C/W = 21.6 °C above the solder point. If the solder point is at 85 °C, the junction will be at 106.6 °C, which is safe. However, derating may be needed at higher ambient temperatures.

Q: What is the typical forward voltage at 20 mA?
A: The typical forward voltage is 2.0 V, but it can range from 1.8 V to 2.4 V depending on the bin. Design your circuit to accommodate this spread.

Q: Can I use this LED for exterior automotive lighting?
A: The datasheet specifies approval only for automotive interior. Exterior applications may require additional qualifications (e.g., AEC-Q102). However, the chip itself may be usable if properly protected from moisture and thermal stress.

Q: How should I clean the PCB after soldering?
A: Use isopropyl alcohol. Avoid ultrasonic cleaning as it can damage the LED. If other solvents are used, verify compatibility with the silicone encapsulation.

11. Real-World Usage Case Studies

11.1 Dashboard Ambient Lighting Module

A tier-1 automotive supplier designed a linear light guide for dashboard ambient strips using 12 RF-OMRB14TS-AK LEDs spaced at 10 mm intervals. Each LED was driven at 15 mA to achieve 400 mcd per segment. The wide 120° viewing angle ensured uniform brightness along the guide without hot spots. The module passed 1000-hour life tests at 85 °C/85% RH with less than 10% lumen depreciation.

11.2 Center Console Backlighting

In a center console design, the LED was used as a direct backlight for capacitive touch buttons. A diffuser film was placed 3 mm above the LED. The resulting luminance exceeded 500 cd/m² at 20 mA. The high flux density of 800 mcd per LED allowed the use of fewer components compared to older-generation LEDs, reducing costs.

12. Principle Explanation

The RF-OMRB14TS-AK uses AlGaInP (aluminum gallium indium phosphide) as the active layer material. When a forward bias is applied, electrons and holes recombine in the quantum well region, emitting photons with energy corresponding to the red part of the spectrum. The bandgap of AlGaInP can be tuned by adjusting the aluminum and indium composition; for red emission around 615 nm, the composition is optimized to achieve high internal quantum efficiency. The substrate (likely GaAs or GaP) is transparent to the emitted light, allowing light extraction from the bottom as well. The PLCC-2 package uses a transparent silicone encapsulant to protect the chip and serve as a lens. The cathode and anode are connected via silver-plated leadframes.

13. Development Trends

The automotive LED market is moving toward higher efficiency and smaller packages. Future iterations of this product family may offer even higher luminous efficacy (e.g., >50 lm/W) through improved epitaxial design and better current spreading. Additionally, integration of ESD protection diodes in the package could simplify board-level design. The trend towards miniLED and microLED backlighting may eventually reach automotive interior, but PLCC-2 packages remain cost-effective for large-volume ambient lighting. Compliance with future automotive reliability standards (e.g., AEC-Q102 for photobiological safety) will be necessary.