Red LED 3.2x1.25x1.1mm - Forward Voltage 2.0V - Current 30mA - Power 72mW - English Technical Datasheet

1. Product Overview

1.1 General Description

This red SMD LED is fabricated using a red light-emitting diode chip and packaged in a standard 3.2mm x 1.25mm x 1.1mm surface-mount package. The device is designed for general indication, signage, and display applications requiring high brightness and wide viewing angle. With a compact footprint, it is suitable for automated SMT assembly and reflow soldering processes.

1.2 Features

• Extremely wide viewing angle: 140 degrees (half-power angle), enabling clear visibility from multiple directions.
• Compatible with all SMT assembly and solder processes, including lead-free reflow.
• Moisture sensitivity level (MSL): Level 3 per JEDEC standard, requiring proper handling and baking before use if exposed to ambient conditions beyond specified limits.
• RoHS compliant, free of hazardous substances such as lead, mercury, cadmium, and hexavalent chromium.
• Available in multiple brightness and wavelength bins for design flexibility.

1.3 Applications

• Optical indicators and status lights in consumer electronics, industrial equipment, and automotive interiors.
• Switches and symbol backlighting, such as in keyboards, control panels, and signage.
• General lighting and decorative applications where compact size and low power consumption are desired.

2. Technical Parameters

2.1 Electrical and Optical Characteristics (Ta = 25°C)

The following table summarizes the key electrical and optical parameters measured at a forward current of 20 mA and ambient temperature of 25°C, unless otherwise noted.

Note: Forward voltage measurement tolerance: ±0.1 V. Dominant wavelength measurement tolerance: ±2 nm. Luminous intensity measurement tolerance: ±10%.

2.2 Absolute Maximum Ratings

Stresses beyond those listed in the table below may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated in the recommended operating conditions is not implied.

The maximum allowed forward current must be derated if the thermal resistance and ambient temperature cause the junction temperature to exceed 95°C. Adequate heat sinking or reduced drive current should be employed under high-temperature conditions.

3. Binning System

The LED is offered in multiple bins for forward voltage (VF), dominant wavelength (λD), and luminous intensity (IV). This binning allows designers to select devices with tight parameter tolerances for consistent performance across a lighting system.

3.1 Forward Voltage Bins

Three VF bins are defined: B0 (1.8–2.0 V), C0 (2.0–2.2 V), and D0 (2.2–2.4 V). The typical forward voltage at 20 mA is around 2.0 V for the B0 bin.

3.2 Dominant Wavelength Bins

Three dominant wavelength bins are available: F00 (625–630 nm, deep red), G00 (630–635 nm, red), and H00 (635–640 nm, orange-red). The typical peak emission is around 630 nm.

3.3 Luminous Intensity Bins

The luminous intensity is categorized into three ranges: 1BS (40–90 mcd), 1DN (90–140 mcd), and 1GK (140–200 mcd). These bins enable matching of brightness in multi-LED applications.

The bin code is printed on the package label, along with other identifiers such as lot number and date code.

4. Performance Curves

Typical optical and electrical characteristics are shown in the curves below. These curves are intended as design guidelines; actual performance may vary with operating conditions.

4.1 Forward Voltage vs. Forward Current (Fig. 1-6)

The plot shows the exponential relationship typical of a diode. At 20 mA, the forward voltage is approximately 2.0 V. The curve can be used to estimate current for a given voltage, but a current-limiting resistor is always recommended.

4.2 Forward Current vs. Relative Intensity (Fig. 1-7)

Relative luminous intensity increases nearly linearly with forward current up to 30 mA. Slight saturation may occur at higher currents due to heating.

4.3 Pin Temperature vs. Relative Intensity (Fig. 1-8)

As the solder point temperature rises, the relative output decreases. At 85°C, the intensity is about 90% of that at 25°C. Thermal management is essential to maintain consistent light output.

4.4 Pin Temperature vs. Forward Current (Fig. 1-9)

The maximum allowable forward current must be derated as pin temperature increases. At 85°C, the maximum current is reduced to approximately 20 mA to keep the junction temperature below 95°C.

4.5 Forward Current vs. Dominant Wavelength (Fig. 1-10)

Dominant wavelength shifts slightly with increasing current, typically less than 2 nm over the operating range. This is due to band-filling effects in the semiconductor.

4.6 Relative Intensity vs. Wavelength (Fig. 1-11)

The spectral power distribution peaks at approximately 630 nm, with a spectral half-bandwidth of 15 nm (typical). This ensures a saturated red color.

4.7 Radiation Pattern (Fig. 1-12)

The LED exhibits a wide lambertian radiation pattern with a half-power angle of 140°. This makes it ideal for applications requiring broad illumination or wide-angle indication.

5. Mechanical and Packaging Information

5.1 Package Dimensions

The package body measures 3.2 mm (length) x 1.25 mm (width) x 1.1 mm (height). Two solder pads are provided on the bottom surface. The anode pad is marked with a plus sign or identifier in the drawing. Detailed mechanical drawings can be found in the datasheet (Fig. 1-1 to 1-5).

5.2 Recommended Soldering Pattern

The recommended copper pad dimensions for reflow soldering are shown in the datasheet. Adequate pad size ensures good thermal and electrical contact. A solder paste stencil thickness of 0.12 mm is generally recommended.

5.3 Polarity Identification

The cathode side is typically marked by a notch or flat on the package. On the bottom view, pad 1 is the anode and pad 2 is the cathode (as per Fig. 1-4). Correct polarity must be observed during assembly.

6. SMT Reflow Soldering

6.1 Reflow Profile

The recommended reflow soldering profile is based on JEDEC standards. The key parameters are:

• Average ramp-up rate (Tsmax to TP): maximum 3°C/s
• Preheat temperature range (Tsmin to Tsmax): 150°C to 200°C
• Preheat time (ts): 60 to 120 seconds
• Time above 217°C (tL): 60 to 150 seconds
• Peak temperature (TP): 260°C (maximum)
• Time within 5°C of peak temperature (tp): maximum 30 seconds
• Time at peak temperature (>255°C): maximum 10 seconds
• Average cooling rate: maximum 6°C/s
• Time from 25°C to peak temperature: maximum 8 minutes

Reflow soldering should not be performed more than twice. If more than 24 hours elapse between two soldering cycles, the LEDs may absorb moisture and should be baked prior to the second reflow.

6.2 Hand Soldering

If hand soldering is required, the iron tip temperature must be below 300°C and the soldering time should not exceed 3 seconds. Only one hand soldering operation is allowed per LED.

6.3 Rework and Repair

Rework after reflow is not recommended. If unavoidable, a dual-head soldering iron should be used to minimize thermal stress. Pre-qualification testing is necessary to ensure no damage to the LED.

7. Handling Precautions

7.1 Storage

The LEDs are shipped in moisture barrier bags (MBB) with desiccant and humidity indicator card. Before opening the bag, store at ≤30°C and ≤75% RH. After opening, the LEDs must be used within 168 hours (7 days) if stored at ≤30°C and ≤60% RH. If the storage time is exceeded or the humidity indicator card shows pink (indicating moisture absorption), baking is required: 60±5°C for >24 hours.

7.2 Electrostatic Discharge (ESD) Protection

LEDs are sensitive to ESD. Proper ESD precautions should be taken, including grounded workstations, conductive packaging, and antistatic wrist straps. The device is rated for 2000V HBM.

7.3 Chemical and Environmental Considerations

The LED encapsulant is silicone, which is permeable to certain gases and chemicals. Sulfur compounds in the environment or in mating materials should be kept below 100 ppm. Bromine and chlorine contents in external materials should each be less than 900 ppm, and their total less than 1500 ppm. Volatile organic compounds (VOCs) can outgas and deposit on the LED, causing discoloration and light loss. Adhesives used near the LED must not emit organic vapors.

7.4 Mechanical Handling

Do not apply pressure directly on the silicone lens. Use tweezers to handle the component by the side surfaces. Avoid bending the PCB after soldering, as this may crack the LED package.

7.5 Cleaning

Isopropyl alcohol is recommended for cleaning. Other solvents must be tested for compatibility with the silicone encapsulant. Ultrasonic cleaning is not recommended as it may damage the LED.

8. Packaging and Ordering Information

8.1 Packaging Specification

The LEDs are packaged in tape and reel format: 3000 pieces per reel. The carrier tape is made of conductive plastic and features 8 mm width with a pocket pitch of 4 mm. The reel diameter is 178 mm, with a hub diameter of 60 mm and a tape width of 8 mm.

8.2 Label Information

Each reel carries a label containing the following information: Part Number, Spec Number, Lot Number, Bin Code (including VF, wavelength, and intensity bins), quantity, and date code. The bin code is essential for ensuring consistent performance in production.

8.3 Moisture Resistant Packing

The reels are sealed in a moisture barrier bag with desiccant and a humidity indicator card. The bag is then packed in a cardboard box for shipment.

9. Reliability and Testing

9.1 Reliability Test Conditions

The product has been qualified according to JEDEC standards. The following tests were performed with 22 samples each, acceptance criteria: 0 failures allowed (Ac=0, Re=1).

9.2 Failure Criteria

The following criteria define a failure after reliability testing:

• Forward voltage (VF) exceeds 1.1 times the upper specification limit (U.S.L.)
• Reverse current (IR) exceeds 2.0 times the upper specification limit (U.S.L.)
• Luminous flux (Φ) drops below 0.7 times the lower specification limit (L.S.L.)

10. Application Notes

When designing LED circuits, always include a current-limiting resistor to prevent overcurrent. The resistor value can be calculated as R = (V_supply - VF_typ) / IF_desired. For example, with a 5V supply and target current of 20 mA, R = (5 - 2.0) / 0.02 = 150 Ω. Use the worst-case VF min/max to ensure safe operation under all conditions.

For series or parallel connections, consider current sharing and thermal effects. LEDs of the same bin should be used in parallel to minimize brightness variation. Adequate PCB copper area should be provided for heat dissipation, especially when operating at higher currents or ambient temperatures.

The wide viewing angle makes this LED suitable for edge-lighting and backlighting applications where uniform illumination is desired.

11. Frequently Asked Questions

Q: Why does the LED brightness decrease as temperature increases?

A: The internal quantum efficiency of the semiconductor decreases with temperature, leading to lower light output at the same drive current. Thermal management is key.

Q: Can I drive the LED directly from a voltage source?

A: No, a current-limiting resistor or constant-current driver is mandatory to avoid damaging the LED.

Q: What happens if reverse voltage is applied?

A: Reverse voltages above the breakdown can cause leakage current and eventually destroy the LED. The maximum reverse voltage is 5V test condition; prolonged reverse bias should be avoided.

Q: How should I store unused LEDs?

A: Store in original moisture barrier bag at ≤30°C and ≤75% RH. If opened, use within 168 hours or bake before use.

Q: Is the LED compatible with lead-free soldering?

A: Yes, the peak temperature of 260°C is compatible with RoHS-compliant lead-free soldering processes.

12. Working Principle

An LED is a semiconductor diode that emits light when electrons recombine with holes in the PN junction. In this red LED, the active region is typically made of aluminum gallium indium phosphide (AlGaInP) or gallium arsenide phosphide (GaAsP) materials. When forward biased, electrons from the n-side and holes from the p-side recombine in the active region, releasing energy in the form of photons. The wavelength of the emitted light corresponds to the bandgap energy of the semiconductor material—in this case, around 1.96 eV for red light (630 nm). The LED is encapsulated in a clear or tinted silicone lens that also provides protection and shapes the radiation pattern.

13. Development Trends

Red LEDs continue to evolve with higher efficiency (higher lm/W) and better thermal stability. The trend is toward smaller packages (e.g., 3.2×1.25 mm is already compact) and higher brightness bins. Advances in chip technology, such as improved light extraction and flip-chip designs, promise further performance improvements. Additionally, integration with intelligent driving circuits and IoT connectivity is expected to expand applications in smart lighting and displays.