T7C Series 7070 White LED Datasheet - Size 7.0x7.0x2.8mm - Voltage 49V - Power 8.82W - English Technical Document

1. Product Overview

The T7C series represents a high-performance, top-view white LED designed for demanding general lighting applications. This device utilizes a thermally enhanced package design to facilitate efficient heat dissipation, which is critical for maintaining performance and longevity. The compact 7070 footprint (7.0mm x 7.0mm) houses a high-output LED chip capable of operating at elevated drive currents. Its primary advantages include high luminous flux output, robust current handling capability, and a wide viewing angle, making it suitable for a variety of illumination tasks. The product is intended for architectural and decorative lighting, retrofit solutions, general illumination, and indoor/outdoor signage backlighting. It is compliant with RoHS directives and is suitable for lead-free reflow soldering processes.

2. In-Depth Technical Parameter Analysis

2.1 Electro-Optical Characteristics

The core performance of the LED is defined at a junction temperature (Tj) of 25°C and a forward current (IF) of 180mA. The luminous flux output varies significantly with Correlated Color Temperature (CCT) and Color Rendering Index (CRI). For instance, a 6500K LED with a CRI of 70 (Ra70) offers a typical luminous flux of 1430 lumens, with a minimum guaranteed value of 1300 lumens. As CRI increases to 90 (Ra90), the typical output decreases to 1160 lumens, with a 1000-lumen minimum, illustrating the trade-off between color quality and light output. All luminous flux measurements have a tolerance of ±7%, while CRI measurements have a tolerance of ±2.

2.2 Electrical and Thermal Parameters

The absolute maximum ratings establish the operational limits. The maximum continuous forward current (IF) is 200mA, with a pulsed forward current (IFP) of 300mA allowed under specific conditions (pulse width ≤100μs, duty cycle ≤1/10). The maximum power dissipation (PD) is 10.4W. The device can operate in ambient temperatures ranging from -40°C to +105°C. The typical forward voltage (VF) at 180mA is 49V, with a range from 46V to 52V (±3% tolerance). A key thermal parameter is the junction-to-solder point thermal resistance (Rth j-sp), which is typically 1.5°C/W. This low value is indicative of the package's effective thermal management design, crucial for maintaining low junction temperatures at high drive currents.

3. Binning System Explanation

3.1 Luminous Flux Binning

The LEDs are sorted into luminous flux bins based on their measured output at 180mA. Each CCT/CRI combination has a specific set of bin codes. For example, a 4000K LED with Ra70 can be found in bins 3D (1300-1400 lm), 3E (1400-1500 lm), 3F (1500-1600 lm), and 3G (1600-1700 lm). This binning allows designers to select components with consistent brightness for uniform lighting applications.

3.2 Forward Voltage Binning

To aid in circuit design for consistent current drive, LEDs are also binned by forward voltage. The bins are 6R (46-48V), 6S (48-50V), and 6T (50-52V). Selecting LEDs from the same voltage bin can help ensure uniform current distribution in parallel configurations.

3.3 Chromaticity Binning

The color consistency is controlled using a 5-step MacAdam ellipse system, which groups LEDs with very similar chromaticity coordinates (x, y). Specific center points and ellipse parameters are defined for each CCT (e.g., 27 for 2700K, 65 for 6500K). This tight binning, aligned with standards like Energy Star for 2600K-7000K, ensures minimal visible color variation between LEDs in an installation.

4. Performance Curve Analysis

The datasheet includes several graphical representations of performance. The Relative Luminous Flux vs. Forward Current curve (Fig. 5) shows how light output increases with current, typically in a sub-linear fashion at higher currents due to efficiency droop. The Forward Voltage vs. Forward Current curve (Fig. 6) depicts the diode's IV characteristic. The Relative Luminous Flux vs. Solder Point Temperature curve (Fig. 7) and Forward Voltage vs. Solder Point Temperature curve (Fig. 8) are critical for understanding thermal derating; light output decreases and forward voltage slightly decreases as temperature rises. The CIE x, y coordinate shift with temperature (Fig. 9) shows how the perceived color may change. Finally, the Maximum Forward Current vs. Ambient Temperature curve (Fig. 10) provides guidance for derating the drive current in high-temperature environments to prevent overheating.

5. Mechanical and Package Information

The LED package has dimensions of 7.0mm in length and width, with a height of approximately 2.8mm. A detailed dimensioned drawing shows the top view, side view, and solder pad layout. The cathode and anode are clearly marked. The recommended solder pad pattern is provided to ensure reliable mechanical and thermal connection to the printed circuit board (PCB). The package is designed to be mounted on a Metal Core PCB (MCPCB) for optimal heat sinking. The tolerance for unspecified dimensions is ±0.1mm.

6. Soldering and Assembly Guidelines

The device is rated for lead-free reflow soldering. The maximum soldering temperature is specified as 230°C or 260°C for a duration of 10 seconds. It is crucial to follow the recommended reflow profile to avoid thermal shock and damage to the LED package or the internal die attach. Care must be taken during handling to avoid electrostatic discharge (ESD), as the device has an ESD withstand rating of 1000V (Human Body Model). The storage temperature range is -40°C to +85°C.

7. Packaging and Ordering Information

The part numbering system is detailed and follows the format: T [X1][X2][X3][X4][X5][X6]-[X7][X8][X9][X10]. Key elements include: X1 (Type code, '7C' for 7070), X2 (CCT code, e.g., '27' for 2700K), X3 (CRI code, '7' for Ra70, '8' for Ra80, '9' for Ra90), X4 (Number of serial chips), X5 (Number of parallel chips), and X6 (Component code). This flexible system allows for precise identification of the LED's electrical and optical characteristics.

8. Application Recommendations

8.1 Typical Application Scenarios

Due to its high flux output and power handling, this LED is ideal for applications requiring high brightness in a compact source. This includes downlights, high-bay lighting, street lighting modules, and architectural facade lighting. Its wide viewing angle (120° half-intensity angle) makes it suitable for area lighting where broad illumination is needed.

8.2 Design Considerations

Thermal Management: The low thermal resistance (1.5°C/W) is only effective if the LED is properly heatsinked. Designers must use an appropriate MCPCB and possibly an external heatsink to keep the solder point temperature within safe limits, especially when driving at or near the maximum current. Refer to Fig. 10 for current derating.
Electrical Drive: A constant current driver is mandatory for reliable operation. The high forward voltage (~49V) means drivers must be selected accordingly. For designs using multiple LEDs in series, the total voltage requirement can be significant.
Optical Design: Secondary optics (lenses, reflectors) may be required to achieve the desired beam pattern. The wide viewing angle is a starting point for optical system design.

9. Technical Comparison and Differentiation

Compared to smaller packages like 5050 or 3030 LEDs, the 7070 format offers significantly higher total light output and power dissipation capability in a single package, simplifying optical design and reducing the part count in some applications. The specified thermal resistance is competitive, indicating a package designed for high-power operation without excessive temperature rise. The comprehensive binning for flux, voltage, and chromaticity provides a level of consistency that is essential for professional lighting products, differentiating it from components with looser tolerances.

10. Frequently Asked Questions (Based on Technical Parameters)

Q: What is the actual power consumption of this LED?
A: At the typical operating point of 180mA and 49V, the electrical power input is approximately 8.82 Watts (0.18A * 49V).
Q: How does light output change with temperature?
A: As shown in Fig. 7, relative luminous flux decreases as the solder point temperature increases. Proper heatsinking is critical to maintain output.
Q: Can I drive this LED at 200mA continuously?
A: While 200mA is the absolute maximum rating, continuous operation at this current requires excellent thermal management to keep the junction temperature below 120°C. Derating per Fig. 10 is recommended for reliable long-term operation.
Q: What driver voltage do I need for 3 LEDs in series?
A: Assuming typical Vf of 49V per LED, the driver should provide at least 147V, plus some headroom for regulation.

11. Practical Design and Usage Cases

Case 1: High-Bay Industrial Light: A fixture uses 4 of these LEDs on a single large MCPCB attached to an extruded aluminum heatsink. Driven at 150mA each by a constant current driver, they provide high-efficiency, high-CRI illumination for a warehouse. The tight chromaticity binning ensures uniform white light across the fixture.
Case 2: Modular Street Light: A street light module is constructed with 12 LEDs arranged in a circular pattern. Each LED is paired with a individual secondary optic to create a specific street-lighting distribution pattern (e.g., Type II or Type III). The high lumen output per LED reduces the number of components needed.

12. Operating Principle Introduction

This is a phosphor-converted white LED. The core is a semiconductor chip (typically based on indium gallium nitride) that emits blue light when electrical current passes through it in the forward direction. This blue light is partially absorbed by a phosphor coating (cerium-doped yttrium aluminum garnet, or YAG, is common) deposited on or around the chip. The phosphor re-emits this energy as a broad spectrum of yellow light. The combination of the remaining blue light and the converted yellow light appears white to the human eye. The exact ratio of blue to yellow, and the specific phosphor composition, determines the CCT and CRI of the emitted white light.

13. Technology Trends

The general trend in high-power LED packaging like the 7070 format is towards ever-higher luminous efficacy (lumens per watt), improved color rendering across all CCTs, and enhanced reliability at higher operating temperatures. There is also a focus on improving the package's ability to handle higher current densities and optical flux densities. Furthermore, standardization of footprints and electrical interfaces continues to simplify design for lighting manufacturers. The move towards more precise and consistent binning, as seen in this datasheet, is a key trend enabling high-quality, uniform lighting solutions.