What is the difference between LED bead copper bracket and iron bracket? Explain in one article how to choose
What is the difference between some manufacturers reporting 0.03 yuan and others reporting 0.08 yuan for the same 5mm red light? Besides chips and gold wires, the biggest variable isBracket material——Copper bracket or iron bracket. This difference cannot be seen without disassembling the lamp beads, but it directly determines the heat dissipation, lifespan, and batch stability of the lamp beads.
This article explains the difference between copper and iron brackets from the perspective of packaging factories.
1、 What does a bracket do
The bracket for direct insertion and surface mount LED (also known as the lamp cup/head frame) serves three functions:
1. Carrier chipAnd provide reflective cups
2. conduct electricityConnect external pins to gold wires
3. thermal conductionExport the junction temperature of the chip to the PCB and air
The third point is the most crucial. The light decay rate of LED is strongly correlated with junction temperature - for every 10 ℃ increase in junction temperature, the lifespan is approximately halved. The bracket is the first channel for chip heat escape.
2、 Copper bracket vs iron bracket: comparison of hard parameters
| Comparison item | Copper bracket (brass/purple copper silver plated) | Iron bracket (silver plated iron) |
|---|---|---|
| thermal conductivity | About 380 W/(m · K) (purple copper) | About 80 W/(m · K) |
| Electrical conductivity | Excellent | General |
| Thermal resistance (same packaging) | 30% -50% lower | high |
| cost | High (material price difference can reach several times) | low |
| Typical junction temperature performance | 5-15 ℃ lower under the same current | relatively high |
| Long term light decay | slow | Fast |
| mechanical strength | Soft, not easy to break when bent | Hard, prone to brittle fracture after repeated bending |
One sentence conclusion:Copper bracket has good heat dissipation, slow light decay, and long service life; Iron brackets are cheap, but the heat is trapped in the chip, and long-term illumination significantly accelerates light decay.
3、 How to distinguish? Three practical methods
1. The magnet method (only applicable for preliminary screening of direct insertion lamp beads)
The iron bracket is magnetic, and a small magnet can attract the pins; Copper brackets are non-magnetic. Attention: This is a coarse screening, and the results of the alloy bracket may not be typical and may not be easy to handle for surface mount light beads.
2. Bending foot feel
Copper pins are soft, easy to bend and not easily broken, and can be repeatedly bent; The iron pins are hard and brittle, and there is a sound of breakage when bent twice.
3. Comparison of actual lighting (most reliable)
Take 20 pieces each, light up 20mA for 30 minutes, and use an infrared thermometer to measure the temperature at the root of the pins. The overall temperature of the copper bracket is more uniform and the temperature rise of the pins is significant (heat is dissipated); The heat of the iron bracket is concentrated in the colloidal head. Perform another 168 hour accelerated aging comparison with light decay, and the differences are clear at a glance.
4、 What scenarios require copper brackets
- Long term illumination(Over 8 hours per day): Equipment status lights, hallway indicators, security equipment
- High temperature environmentInternal chassis, car mounted, outdoor sun exposed panels
- High brightness/high current driveIn situations where the usage is close to the rated upper limit
- Projects with a commitment to light decayFor example, the contract stipulates that the time decay within 5000 hours should not exceed 10%
What scenarios can iron brackets also be used in: short lit toys, low-cost consumer electronics, and occasions requiring a lifespan of 1-2 years. The cost-effectiveness of iron brackets is reasonable——The premise is that the seller truthfully informs.
5、 Suggestions for purchasing anti pit measures
1. Specification bookClearly state the material of the bracket in black and white(Copper/Iron, Coating Process), any unclear information should be understood as an iron bracket
If the quotation for the same model is significantly lower than the market price by more than 30%, first ask about the bracket material and gold wire material (alloy wire is also a common cost reduction point)
3. Conduct a 168 hour aging comparison before batch production, and the data is more reliable than verbal promises
The indicator light beads of Hongcheng Optoelectronics are used throughout the entire lineCopper bracket+99.99% pure gold wireEncapsulation, the specification sheet clearly indicates the bracket material, thermal resistance, and light attenuation curve, supporting customers to provide samples for third-party testing and comparison.
VI FAQ
Q: Why do copper bracket light beads also experience rapid light decay?
The bracket is just one link in the heat dissipation chain. The quality of chips, the solidification process, the temperature resistance of phosphors and adhesives also affect light decay. The combination of copper bracket and miscellaneous chips is still unreliable, and the selection of materials depends on the overall situation.
Q: Can iron bracket light beads be remedied by increasing the heat dissipation solder pads?
Partial improvement is possible, but the thermal bottleneck of the bracket body is inside the lamp beads, and external heat dissipation cannot be restored. It is not recommended for high current scenarios.
Q: Is there a difference between red copper, brass, and purple copper brackets?
have Purple copper (pure copper) has the best thermal conductivity, while brass (copper zinc alloy) has better strength and slightly lower cost. Mainstream quality lamp beads often use brass silver plated brackets, which balance thermal conductivity and weldability.
7、 Summary
The essential difference between copper brackets and iron brackets isheat dissipation capacityUltimately manifested asLight decay rate and service lifeChoose copper brackets for long-term lighting, high temperature, and high brightness scenes; The specification sheet clearly states the material and aging test verification, which are two safeguards to avoid bracket tampering.
Please contact Hongcheng Optoelectronics at 139 2571 4318 (WeChat ID) for specifications and sample testing of copper bracket LED beads, sales@led-hc.com .
