With the rapid development of the commercial display industry in recent years, LED display is an indispensable part of it, and its technological innovation is changing with each passing day. Among many technologies, SMD (Surface Mount Device) packaging technology and COB (Chip on Board) packaging technology are particularly eye-catching. Today, we'll take a look at the differences between the two technologies and give you a taste of their respective charms.

First, let's start with the technology. SMD packaging technology is a form of electronic component packaging. SMD, full name Surface Mounted Device, means surface mount device. It is a technology widely used in the electronics manufacturing industry to package integrated circuit chips or other electronic components for mounting directly on the surface of a PCB (printed circuit board).

SMD package Main features:

Small size: SMD packaged components are small in size and can achieve high-density integration, which is conducive to the design of miniaturized and lightweight electronic products.

Light weight: Because SMD package components do not require pins, the overall structure is lightweight, suitable for applications requiring light weight.

Good high frequency performance: The short pins and short connection paths of SMD package components help reduce inductance and resistance and improve high frequency performance.

Easy to automate production: SMD packaging components are suitable for the production of automated SMT machines, improving production efficiency and quality stability.

Good thermal performance: Led SMD package components are in direct contact with the PCB surface, which is conducive to heat dissipation and improves the thermal performance of the components.

Easy servicing and maintenance: The surface mount of SMD packaged components makes servicing and replacing components easier.

Package type: There are many types of SMD packages, including SOIC, QFN, BGA, LGA, and so on. Each package type has its specific advantages and application scenarios.

Technology development: Since its introduction, SMD packaging technology has developed into one of the mainstream packaging technologies in the electronics manufacturing industry. With the advancement of science and technology and the needs of the market, SMD packaging technology is also constantly evolving to meet the needs of higher performance, smaller size and lower cost.

COB packaging technology, full name Chip on Board, is a packaging technology that welds the chip directly on the Printed Circuit Board (PCB). This technology is mainly used to solve the LED heat dissipation problem, and to achieve the tight integration of the chip and the circuit board.

Technical principle: COB package is the bare chip with conductive or non-conductive adhesive attached to the interconnect substrate, and then lead bonding to achieve its electrical connection. During the packaging process, if the bare chip is directly exposed to the air, it is vulnerable to contamination or human damage, so the chip and bond leads are usually wrapped with glue to form a so-called "soft encapsulation".

Compact package: Because the package and PCB are combined together, the chip size can be greatly reduced, the integration can be improved, and the circuit design can be optimized, the circuit complexity can be reduced, and the system stability can be improved.

Good stability: The chip is welded directly on the PCB, so the vibration resistance and impact resistance is good, and it can also maintain stability in high temperature, humidity and other harsh environments, and extend the product life.

Good thermal conductivity: The use of thermal conductive glue between the chip and the PCB can effectively improve the heat dissipation effect, reduce the influence of heat on the chip, and improve the service life of the chip.

Low manufacturing cost: no pins are needed, eliminating some complex processes of connectors and pins in the manufacturing process, and reducing the preparation cost. At the same time, it can realize automated production, reduce labor costs and improve manufacturing efficiency.

Note: Maintenance difficulties: Because the chip and PCB are welded directly, it is impossible to disassemble or replace the chip separately, and generally the entire PCB needs to be replaced, which increases the cost and maintenance difficulty.

Reliability dilemma: The chip is embedded in the adhesive, and the digestion process is easy to damage the micro-dismantling frame, which may cause the lack of pad and affect the tendency of production.

High environmental requirements in the production process: COB packaging does not allow dust, static electricity and other pollution factors in the workshop environment, otherwise it is easy to lead to an increase in the failure rate.

In general, COB packaging technology of Led Screen is a cost-effective, excellent technology, in the field of intelligent electronics has a wide range of application potential. With the further improvement of technology and the expansion of application scenarios, COB packaging technology will continue to play an important role.

So, what's the difference between these two technologies?

Visual experience: COB display with its surface light source characteristics, for the audience to bring a more delicate, uniform visual experience. Compared with SMD point light sources, COB is more vivid in color performance, more excellent in detail processing, and more suitable for long-term close viewing.

Stability and maintenance: Although the SMD display is convenient for on-site maintenance, its overall protection is weak and easy to be affected by the external environment. The COB display has a higher level of protection due to its overall package design, and better waterproof and dustproof performance. However, it should be noted that in the event of a failure, the COB display usually needs to be returned to the factory for repair.

Power consumption and energy efficiency: Because COB uses an unobtrusive flip process, its light source is more efficient and its power consumption is lower at the same brightness, which saves users' electricity expenses.

Cost and development: SMD packaging technology is widely used in the market due to its high maturity and low production cost. Although the COB technology has lower theoretical cost, the actual cost is still relatively high due to its complex production process and low yield. However, with the continuous progress of technology and the expansion of production capacity, the cost of COB is expected to be further reduced.

Today, in the commercial display market, COB and SMD packaging technologies have their own strengths. With the growing demand for high-definition display, Micro LED display products with higher pixel density are gradually favored by the market. COB technology has become one of the key technologies to achieve the high pixel density of Micro LED because of its high integrated packaging characteristics. At the same time, with the continuous reduction of LED screen spacing, the cost advantage of COB technology is also becoming increasingly prominent.

In the future, with the continuous progress of technology and the continuous maturity of the market, COB and SMD packaging technology will continue to play an important role in the commercial display industry. We have reason to believe that in the near future, these two technologies will jointly promote the development of the commercial display industry to a higher, smarter and more environmentally friendly direction. Let's wait and see to witness this exciting moment together!