Ceramic 3535 Series 1W Green LED Datasheet - Dimensions 3.5x3.5x?mm - Voltage 3.5V - Power 1W - English Technical Document

1. Product Overview

This document provides the complete technical specifications for a high-power Ceramic 3535 series 1W Green Light Emitting Diode (LED). The ceramic substrate offers superior thermal management compared to traditional plastic packages, enabling higher drive currents and improved long-term reliability. This LED is designed for applications requiring high brightness and stable performance in demanding environments.

1.1 Product Identification and Naming Convention

The product model is identified as T1901PGA. The naming convention follows a structured code: T □□ □□ □ □ □ – □□□ □□. This code breaks down into several key parameters:

• Package Code (19): Indicates a Ceramic 3535 package.
• Chip Count Code (P): Denotes a single high-power LED chip.
• Color Code (G): Specifies Green emission.
• Optics Code (A): Details the lens or optical design (specifics implied by code).
• Flux Bin Code: A multi-digit code defining the luminous flux output bin.
• Color Temperature / Wavelength Bin Code: A code specifying the dominant wavelength range.

Other color codes defined in the system include Red (R), Yellow (Y), Blue (B), Purple (U), Orange (A), IR (I), Warm White L (<3700K), Neutral White C (3700-5000K), and Cool White W (>5000K).

2. Mechanical and Optical Specifications

2.1 Physical Dimensions and Layout

The LED utilizes a Ceramic 3535 surface-mount package. The exact dimensional drawing shows the top view and side profile with critical measurements. Key dimensions include the overall package size of 3.5mm x 3.5mm. The recommended land pattern (footprint) and stencil design for PCB assembly are provided to ensure proper soldering and thermal performance. Tolerances are specified as ±0.10mm for .X dimensions and ±0.05mm for .XX dimensions.

2.2 Optical Characteristics

The primary optical parameters are measured at a standard test current of 350mA and a solder point temperature (Ts) of 25°C.

• Dominant Wavelength (λd): 525 nm (Typical).
• Viewing Angle (2θ1/2): 120 degrees, providing a wide, Lambertian-like emission pattern suitable for area lighting.
• Luminous Flux: The value depends on the specific flux bin assigned to the unit (see Section 3.3).

3. Electrical and Thermal Parameters

3.1 Absolute Maximum Ratings

Stresses beyond these limits may cause permanent damage. All values are specified at Ts=25°C.

• Continuous Forward Current (IF): 500 mA
• Peak Forward Pulse Current (IFP): 700 mA (Pulse width ≤10ms, Duty Cycle ≤1/10)
• Power Dissipation (PD): 1800 mW
• Operating Temperature (Topr): -40°C to +100°C
• Storage Temperature (Tstg): -40°C to +100°C
• Junction Temperature (Tj): 125°C
• Soldering Temperature (Tsld): Reflow soldering at 230°C or 260°C for a maximum of 10 seconds.

3.2 Typical Electrical Characteristics

Measured at Ts=25°C, IF=350mA.

• Forward Voltage (VF): 3.5 V (Typical), 3.6 V (Maximum)
• Reverse Voltage (VR): 5 V
• Reverse Current (IR): 50 μA (Maximum)

4. Binning and Classification System

To ensure color and brightness consistency in production, LEDs are sorted into bins based on key parameters.

4.1 Luminous Flux Binning

Luminous flux is measured at 350mA. The bins, defined by a letter code, specify a minimum (Min) and typical (Type) value. The tolerance for flux measurement is ±7%.

• Code 1R: Min 55 lm, Type 60 lm
• Code 1S: Min 60 lm, Type 65 lm
• Code 1T: Min 65 lm, Type 70 lm
• Code 1W: Min 70 lm, Type 75 lm
• Code 1X: Min 75 lm, Type 80 lm
• Code 1Y: Min 80 lm, Type 87 lm

4.2 Forward Voltage Binning

Forward voltage is measured at 350mA. The bins ensure electrical compatibility in series/parallel strings. Tolerance is ±0.08V.

• Code 1: 2.8V to 3.0V
• Code 2: 3.0V to 3.2V
• Code 3: 3.2V to 3.4V
• Code 4: 3.4V to 3.6V

4.3 Dominant Wavelength Binning

For green LEDs, the dominant wavelength is binned to control the precise hue of green.

• Code G5: 519 nm to 522.5 nm
• Code G6: 522.5 nm to 526 nm
• Code G7: 526 nm to 530 nm

5. Performance Characteristics and Curves

Graphical data provides deeper insight into the LED's behavior under various conditions.

5.1 Forward Current vs. Forward Voltage (I-V Curve)

The curve shows the exponential relationship between current and voltage. It is crucial for designing the correct current-limiting driver. The typical VF of 3.5V at 350mA is confirmed on this graph.

5.2 Relative Luminous Flux vs. Forward Current

This graph illustrates how light output increases with drive current. It typically shows a sub-linear increase at higher currents due to efficiency droop and thermal effects, highlighting the importance of thermal management for maintaining brightness.

5.3 Relative Spectral Power vs. Junction Temperature

The spectral output of an LED shifts with junction temperature. For green LEDs, the peak wavelength generally decreases (blue-shifts) slightly as temperature increases. This graph quantifies that shift, which is important for color-critical applications.

5.4 Spectral Power Distribution

The curve displays the intensity of light emitted across the visible spectrum for this green LED, centered around 525nm. It shows a relatively narrow spectral bandwidth typical of monochromatic LEDs.

6. Assembly and Handling Guidelines

6.1 Soldering Recommendations

The ceramic package is compatible with standard infrared or convection reflow soldering processes. The maximum recommended soldering profile is 230°C or 260°C peak temperature for up to 10 seconds. The provided stencil design ensures the correct solder paste volume for reliable joints and optimal heat transfer from the thermal pad to the PCB.

6.2 Thermal Management

Effective thermal management is critical for performance and lifetime. The ceramic package has a low thermal resistance, but it must be mounted on a PCB with adequate thermal vias and, if necessary, an external heatsink to maintain the junction temperature below 125°C, especially when operating near the maximum current of 500mA.

6.3 ESD Sensitivity

Like all semiconductor devices, LEDs are sensitive to Electrostatic Discharge (ESD). Standard ESD precautions (use of grounded wrist straps, conductive mats, and ionizers) should be observed during handling and assembly.

7. Packaging and Ordering Information

7.1 Tape and Reel Specification

The product is supplied on embossed carrier tape for automated pick-and-place assembly. Detailed drawings specify the pocket dimensions, tape width, reel diameter, and component orientation. The 3535 ceramic package uses a standard tape format compatible with high-speed placement equipment.

7.2 Ordering Code Structure

The complete ordering code is built from the naming convention described in Section 1.1. To order, specify the full code including the package (19), chip count (P), color (G), optics (A), and the desired flux and wavelength bin codes based on the application requirements.

8. Application Notes and Design Considerations

8.1 Typical Applications

• Architectural Lighting: Facade lighting, cove lighting, and accent lighting where high brightness and color stability are needed.
• Automotive Lighting: Interior lighting, signal lights (where color specification is met).
• Portable Lighting: High-end flashlights and work lights.
• Specialty Illumination: Machine vision, stage lighting, and signage.

8.2 Driver Selection

A constant current driver is mandatory for reliable operation. The driver should be selected based on the required forward current (e.g., 350mA for typical use, up to 500mA for maximum output) and the forward voltage bin of the LEDs, especially when connecting multiple devices in series. The driver must have appropriate over-temperature and over-current protection.

8.3 Optical Design

The 120-degree viewing angle is ideal for broad, even illumination. For focused beams, secondary optics (reflectors or lenses) must be designed considering the LED's primary lens and emission pattern. The mechanical drawings provide the necessary datum points for optical alignment.

9. Reliability and Lifetime

While specific L70 or L50 lifetime data (time to 70% or 50% of initial lumen output) is not provided in this excerpt, the ceramic package inherently supports longer lifetime by maintaining a lower junction temperature for a given power dissipation. Lifetime is primarily a function of junction temperature and drive current; operating within the recommended specifications maximizes longevity.

10. Technical Comparison and Advantages

10.1 Ceramic vs. Plastic Package

The ceramic 3535 package offers distinct advantages over standard plastic SMD packages (e.g., PLCC, 5050):

• Superior Thermal Conductivity: Ceramic substrates dissipate heat more efficiently, allowing for higher drive currents and better performance maintenance.
• Enhanced Reliability: Ceramic is resistant to moisture and UV degradation, leading to more stable performance in harsh environments.
• Better Color Stability: Lower operating junction temperature minimizes wavelength shift and lumen depreciation over time.

10.2 High-Power Single Chip Design

Using a single large chip (denoted by 'P') instead of multiple smaller chips improves current density uniformity and can offer better overall efficacy and reliability compared to multi-chip designs at similar power levels.