1608-UG0100M-AM Green LED Datasheet - PLCC-2 Package - 1.6x0.8mm - 2.65V @10mA - 120° Viewing Angle - English Technical Document

1. Product Overview

The 1608-UG0100M-AM is a high-brightness, green light-emitting diode (LED) designed for surface-mount applications. It utilizes a PLCC-2 (Plastic Leaded Chip Carrier) package, which is a common and reliable form factor for SMD LEDs. The primary application focus for this component is automotive interior lighting, indicating its design meets stringent requirements for reliability and performance in challenging environments. Its compact 1608 footprint (1.6mm x 0.8mm) makes it suitable for space-constrained designs where consistent, bright green illumination is required.

The LED's core advantages include a high typical luminous intensity of 700 millicandelas (mcd) at a standard drive current of 10mA, combined with a wide 120-degree viewing angle. This ensures good visibility from various angles, which is crucial for dashboard backlighting, switch illumination, or ambient lighting. Furthermore, the component is qualified according to the AEC-Q101 standard, a critical benchmark for discrete semiconductors in automotive applications, ensuring it can withstand the temperature extremes, vibration, and longevity demands of the automotive industry. Compliance with RoHS, REACH, and halogen-free directives makes it environmentally friendly and suitable for global markets.

2. In-Depth Technical Parameter Analysis

2.1 Photometric and Electrical Characteristics

The key operational parameters define the LED's performance under standard conditions (typically at a junction temperature of 25°C and a forward current of 10mA). The Luminous Intensity (Iv) is specified with a typical value of 700 mcd, a minimum of 520 mcd, and a maximum of 820 mcd. An 8% measurement tolerance is applied. This parameter is the perceived brightness of the light output as seen by the human eye.

The Forward Voltage (Vf) typically measures 2.65V, with a range from 2.25V to 3.25V at 10mA. A tight measurement tolerance of ±0.05V is specified. This voltage drop across the LED is crucial for calculating power dissipation and designing the current-limiting circuitry. The Dominant Wavelength (λd), which defines the perceived color, is centered at 525nm (green) with a range from 520nm to 530nm and a tolerance of ±1nm.

The Viewing Angle is 120 degrees, defined as the off-axis angle where the luminous intensity drops to half of its peak value (Full Width at Half Maximum - FWHM). A tolerance of ±5 degrees is allowed.

2.2 Absolute Maximum Ratings and Thermal Management

These ratings define the limits beyond which permanent damage may occur. The Absolute Maximum Forward Current (IF) is 30mA DC. A higher Surge Current (IFM) of 50mA is permissible for very short pulses (≤10μs) at a low duty cycle (0.005). The device is not designed for reverse voltage operation.

Thermal management is critical for LED longevity. The maximum Junction Temperature (Tj) is 125°C. The component can operate in ambient temperatures from -40°C to +110°C. Two values for Thermal Resistance (Rth JS) are provided: 210 K/W (real, measured) and 190 K/W (electrical, calculated). This parameter indicates how effectively heat travels from the semiconductor junction to the solder point; a lower value is better. The Power Dissipation (Pd) maximum is 97.5 mW, calculated using the maximum forward voltage and current.

The device offers ESD protection up to 2 kV (Human Body Model) and can withstand a reflow soldering peak temperature of 260°C for 30 seconds.

3. Binning System Explanation

To ensure consistency in mass production, LEDs are sorted into performance bins. This datasheet defines bins for three key parameters.

3.1 Luminous Intensity Binning

Luminous intensity is grouped by letter (Q, R, S, T, U, V, A, B) and number (1, 2, 3), with each bin covering a specific mcd range. For the 1608-UG0100M-AM, the possible output bins are highlighted, corresponding to the typical 700mcd specification. This falls within the U2 (520-610 mcd) and U3 (610-710 mcd) or V1 (710-820 mcd) bins, depending on the specific manufacturing lot.

3.2 Dominant Wavelength Binning

Color consistency is managed through dominant wavelength bins. The bins are defined by a 4-digit code representing the minimum and maximum wavelength in nanometers. For this green LED, the relevant bins are in the 520-535nm range, with the specific bin for the 525nm typical part likely being "2025" (520-525nm) or "2530" (525-530nm).

3.3 Forward Voltage Binning

Forward voltage is binned using a 4-digit code representing the minimum and maximum voltage in tenths of a volt (e.g., "2225" means 2.2V to 2.5V). For the typical Vf of 2.65V, the corresponding bins would be "2527" (2.50-2.75V) or "2730" (2.75-3.00V). Knowing the Vf bin helps in designing precise driver circuits, especially for applications requiring uniform brightness across multiple LEDs.

4. Performance Curve Analysis

The provided graphs offer deep insight into the LED's behavior under varying conditions.

4.1 IV Curve and Relative Luminous Intensity

The Forward Current vs. Forward Voltage graph shows the exponential relationship typical of diodes. At 10mA, the voltage is around 2.65V. The curve allows designers to estimate Vf at other drive currents. The Relative Luminous Intensity vs. Forward Current graph shows that light output increases super-linearly with current up to a point. While driving at higher currents increases brightness, it also increases heat and can accelerate lumen depreciation.

4.2 Temperature Dependence

The Relative Luminous Intensity vs. Junction Temperature graph is critical. It shows that as the junction temperature rises, the light output decreases. This is known as thermal quenching. For reliable performance, effective heat sinking and proper drive current management are essential to keep the junction temperature low. The Relative Forward Voltage vs. Junction Temperature graph shows a negative temperature coefficient; Vf decreases as temperature increases. This property can sometimes be used for temperature sensing.

The Dominant Wavelength vs. Junction Temperature graph indicates a slight shift in color (typically a few nanometers) with temperature change, which is important for color-critical applications.

4.3 Derating and Pulse Operation

The Forward Current Derating Curve dictates the maximum allowable continuous forward current based on the solder pad temperature. As the pad temperature increases, the permissible current decreases linearly until it reaches 30mA at 110°C. The graph explicitly states not to use currents below 3mA. The Permissible Pulse Handling Capability chart shows that for very short pulse widths (microseconds to milliseconds), the LED can handle currents significantly higher than the 30mA DC maximum, provided the duty cycle is low enough to prevent overheating.

4.4 Spectral Distribution

The Relative Spectral Distribution graph plots the intensity of light emitted at each wavelength. For a green LED, this shows a peak in the green region (~525nm) with very little emission in other color bands. The narrowness of this peak contributes to the color purity. The Typical Diagram Characteristics of Radiation (polar plot) visually represents the 120-degree viewing angle, showing how intensity distributes spatially.

5. Mechanical, Packaging & Assembly Information

5.1 Mechanical Dimensions and Polarity

The component uses a standard PLCC-2 surface-mount package with a 1608 (1.6mm x 0.8mm) footprint. The mechanical drawing (referenced in the PDF) provides exact dimensions for the package body, lead positions, and lens. Correct polarity is essential. The PLCC-2 package typically has a marked cathode (often a notch, dot, or green mark on the lens or a chamfered corner on the package). The recommended soldering pad layout ensures proper solder joint formation and thermal relief during reflow.

5.2 Soldering and Assembly Guidelines

The LED is rated for reflow soldering with a peak temperature of 260°C for 30 seconds, which aligns with common IPC standards for lead-free soldering. A detailed reflow profile should be followed to avoid thermal shock. Precautions include avoiding mechanical stress on the lens, preventing contamination of the optical surface, and ensuring the use of appropriate solder paste and stencil design. The Moisture Sensitivity Level (MSL) is 2, meaning the component can be stored at ≤30°C/60% RH for up to one year before requiring baking prior to reflow.

5.3 Packaging and Ordering Information

The component is supplied on tape and reel for automated assembly. The packaging information specifies the reel dimensions, tape width, pocket spacing, and orientation. The part number 1608-UG0100M-AM follows a likely coding convention: "1608" for size, "U" for color (likely Ultragreen), "G" for green, "0100" may relate to intensity or version, "M" may indicate packaging, and "AM" likely denotes automotive grade. Ordering information would specify the required bin codes for luminous intensity, wavelength, and forward voltage to ensure the exact performance characteristics are delivered.

6. Application Notes and Design Considerations

6.1 Primary Application: Automotive Interior Lighting

This LED is explicitly designed for automotive interior lighting. This includes applications such as instrument cluster backlighting, center console buttons, ambient footwell lighting, door handle illumination, and gear shift indicators. The AEC-Q101 qualification, wide operating temperature range (-40°C to +110°C), and high reliability make it suitable for these demanding environments where failure is not an option.

6.2 Circuit Design Considerations

Current Driving: LEDs are current-driven devices. A constant current source or a current-limiting resistor in series with a voltage source is mandatory to prevent thermal runaway. The design should be based on the typical Vf and desired If, considering the binning variations.

Thermal Design: The PCB layout should incorporate adequate thermal relief. The solder pads, especially the thermal pad if present, should be connected to a copper pour to dissipate heat. The forward current should be derated according to the expected operating ambient temperature and the thermal resistance of the PCB.

ESD Protection: While the LED has 2kV HBM ESD protection, additional external protection (e.g., TVS diodes or resistors) may be necessary in environments prone to higher ESD events, such as automotive wiring harnesses.

6.3 Optical Design Considerations

The 120-degree viewing angle is suitable for direct viewing or when used with light guides and diffusers. For applications requiring a more focused beam, secondary optics (lenses) would be needed. The green color is effective for status indicators and is often used in combination with other colors for multi-color displays.

7. Technical Comparison and Differentiation

Compared to standard commercial-grade green LEDs, the 1608-UG0100M-AM's key differentiator is its automotive qualification (AEC-Q101). This involves rigorous testing for high-temperature operating life (HTOL), temperature cycling, humidity resistance, and other stresses that generic components do not undergo. Its typical luminous intensity of 700mcd is competitive for its package size. The PLCC-2 package offers better lead rigidity and potentially better thermal performance compared to smaller chip-sized packages like 0402, making it more robust for automotive vibration. The specified binning structure provides designers with predictable performance parameters, which is essential for maintaining consistency in automotive lighting systems where color and brightness matching across multiple units is critical.

8. Frequently Asked Questions (FAQs)

Q: What is the minimum drive current for this LED?
A: The datasheet explicitly states "Do not use current below 3mA." The forward current (IF) has a minimum rating of 3mA. Operating below this may result in unstable or no light output.

Q: Can I drive this LED with a 3.3V supply without a resistor?
A: No. With a typical Vf of 2.65V, connecting it directly to 3.3V would attempt to drive an uncontrolled current through the LED, likely exceeding the absolute maximum rating of 30mA and causing immediate failure. A current-limiting resistor or constant-current driver is always required.

Q: How do I interpret the luminous intensity bin code "U2"?
A: The bin code "U2" refers to a specific luminous intensity range defined in the binning table. For group "U", bin "2" corresponds to a minimum of 520 mcd and a maximum of 610 mcd when measured under standard conditions (IF=10mA, Tj=25°C).

Q: Is this LED suitable for exterior automotive lighting?
A: The datasheet specifies "Automotive Interior Lighting" as the application. Exterior lighting (e.g., tail lights, turn signals) typically requires different packages, higher power, different colors, and often different qualification tests for moisture ingress and UV resistance. This component is not specified for exterior use.

Q: What is the difference between the "Real" and "Electrical" thermal resistance values?
A: The "Real" thermal resistance (210 K/W) is measured directly using physical methods (e.g., temperature sensors). The "Electrical" thermal resistance (190 K/W) is calculated indirectly by measuring the change in forward voltage with temperature (using the Vf temperature coefficient). The electrical method is often faster but can have different assumptions. For conservative thermal design, the higher (real) value should be used.

9. Practical Design and Usage Examples

Example 1: Dashboard Switch Backlighting. A designer needs to illuminate 10 green indicator switches. They plan to drive each LED at 10mA from a 5V rail in the car. Using the typical Vf of 2.65V, the required series resistor value is R = (5V - 2.65V) / 0.01A = 235 Ohms. A standard 240 Ohm resistor would be chosen. The power dissipated in each resistor is (5V-2.65V)*0.01A = 0.0235W, so a small 1/10W resistor is sufficient. The PCB layout would place the LEDs and resistors close together, with thermal vias under the LED's solder pads connected to an internal ground plane for heat spreading.

Example 2: Pulse-Width Modulation (PWM) for Dimming. For ambient lighting that requires brightness control, the LED can be driven with a PWM signal. The forward current during the "on" pulse can be set to 15-20mA to achieve higher peak brightness, while the average current (and thus brightness and heat) is controlled by the duty cycle. The pulse handling capability chart must be consulted to ensure the chosen pulse width and peak current are within safe limits for the selected duty cycle.

10. Operational Principle and Technology Trends

10.1 Basic Operating Principle

A Light Emitting Diode (LED) is a semiconductor p-n junction diode. When a forward voltage is applied, electrons from the n-type material recombine with holes from the p-type material in the active region. This recombination releases energy in the form of photons (light). The specific wavelength (color) of the emitted light is determined by the energy bandgap of the semiconductor materials used (e.g., Indium Gallium Nitride for green). The PLCC package houses the semiconductor die, provides electrical connections via leads, and includes a molded plastic lens that shapes the light output and protects the die.

10.2 Industry Trends

The trend in automotive interior lighting LEDs is towards higher efficiency (more lumens per watt), which reduces power consumption and thermal load. There is also a move towards smaller package sizes (e.g., 1006/0402) for more discreet lighting and tighter integration. Advanced features include integrated driver ICs within the LED package for simplified control. Furthermore, the demand for precise and consistent color rendering across wide temperature ranges is increasing, driving improvements in phosphor technology (for white LEDs) and epitaxial wafer growth consistency (for monochromatic LEDs like this green one). The push for more sophisticated ambient lighting with dynamic multi-color zones also influences the development of LEDs with tighter binning and better performance stability.