The heat dissipation of LED is the biggest headache for LED manufacturers. However, aluminum substrate can be used because aluminum has high thermal conductivity and good heat dissipation, which can effectively export the internal heat. Aluminum substrate is a unique metal based copper clad laminate, which has good thermal conductivity, electrical insulation and machining properties. The PCB should also be close to the aluminum base as far as possible in the design, so as to reduce the thermal resistance caused by the potting adhesive part.
First、 Characteristics of aluminum substrate
1. Surface mount technology (SMT) is adopted;
2. Extremely effective treatment of heat diffusion in the circuit design scheme;
3. Reduce the operating temperature of the product, improve the power density and reliability of the product, and prolong the service life of the product;
4. Reduce product volume and reduce hardware and assembly costs;
5. Replace the fragile ceramic substrate to obtain better mechanical durability.
Second、 Structure of aluminum substrate
Aluminum based copper clad laminate is a metal circuit board material, which is composed of copper foil, thermal insulation layer and metal substrate. Its structure is divided into three layers:
Cireuitl. Layer circuit layer: copper clad laminate equivalent to ordinary PCB, and the thickness of circuit copper foil is LOZ to 10oz.
Dielcctriclayer: the insulating layer is a layer of low thermal resistance and heat conduction insulating material.
Baselayer base: it is a metal substrate, generally aluminum or optional copper. Aluminum based copper clad laminate and traditional epoxy glass cloth laminate.
The circuit layer (i.e. copper foil) is usually etched to form a printed circuit to connect the components. Generally, the circuit layer is required to have great current carrying capacity, so a thicker copper foil with a thickness of 35 should be used μ m~280 μ m； Thermal insulation layer is the core technology of aluminum substrate. It is generally composed of special polymers filled with special ceramics. It has small thermal resistance, excellent viscoelastic performance, anti-aging ability and can withstand mechanical and thermal stress.
This technology is used in the thermal insulation layer of high-performance aluminum substrate, which makes it have extremely excellent thermal conductivity and high-strength electrical insulation; The metal base layer is the supporting component of aluminum substrate, which requires high thermal conductivity. It is generally aluminum plate, and copper plate can also be used (copper plate can provide better thermal conductivity), which is suitable for conventional machining such as drilling, punching, shearing and cutting.
Compared with other materials, PCB has incomparable advantages. Suitable for SMT public art of surface mounting of power components. Without radiator, the volume is greatly reduced, the heat dissipation effect is excellent, and the insulation and mechanical properties are good.
Third、 Purpose of aluminum substrate:
Purpose: Power Hybrid IC (HIC).
1. Audio equipment: input and output amplifiers, balance amplifiers, audio amplifiers, preamplifiers, power amplifiers, etc.
2. Power supply equipment: switch regulator ` DC / AC converter ` SW regulator, etc.
3. Communication electronic equipment: high frequency amplifier ` filter electric appliance ` transmitting circuit.
4. Office automation equipment: motor driver, etc.
5. Automobile: electronic regulator, igniter, power controller, etc.
6. Computer: CPU board, floppy disk drive, power supply device, etc.
7. Power module: converter, solid relay, rectifier bridge, etc.