How packaging technology can help chip miniaturization
When it comes to the packaging of AC-DC power switches, many manufacturers have endless pains and helplessness. The entire AC-DC power supply industry is at the bottom of the technology chain, and it is the most criticized. The existence of the imported laser machine that has been bought in the face of millions of dollars is faced with a variety of packaging requirements. When the manufacturer is facing the world's top laser machine with confidence, it is encapsulated. The old sleeve is the kind of helplessness.
Package means that the circuit pins on the silicon chip are wired to the external connectors for connection with other devices. The package form refers to a case for mounting a semiconductor integrated circuit chip. It not only plays the role of mounting, fixing, sealing, protecting the chip and enhancing the electrothermal performance, but also is connected to the pins of the package by wires on the contacts on the chip, and these pins pass through the wires on the printed circuit board. It is connected to other devices to connect the internal chip to external circuits. Because the chip must be isolated from the outside world to prevent corrosion of the chip circuitry by impurities in the air, the electrical performance is degraded. On the other hand, the packaged chip is also easier to install and transport. It is crucial because the quality of the packaging technology directly affects the performance of the chip itself and the design and manufacture of the PCB (printed circuit board) to which it is connected.
From the innovation direction of power chips, what we have seen in recent years is mainly around some new materials. In addition, modularity has become an important trend, how to achieve low power consumption, small size, high integration, high power. Density has become a common issue for power supply manufacturers.
To what extent does the process of the power chip affect the manufacturer's product definition?
How packaging technology can help chip miniaturization
As far as the product promotion of AC-DC converters is concerned, the same package often faces different power conditions, so it is crucial to select the most suitable converter module power package. Then, what should be paid attention to when selecting the power package of the AC-DC converter to get the best results? Let's take a look at the doorway.
Main considerations when packaging
1, the ratio of chip area to package area is to improve packaging efficiency, as close as possible to 1:1;
2, the pin should be as short as possible to reduce the delay, the distance between the pins as far as possible to ensure that they do not interfere with each other, improve performance;
3. Based on the requirements of heat dissipation, the thinner the package, the better.
The package has undergone the following development process
Structural aspects: TO-"DIP-"LCC-"QFP-"GA-"BGA-"CSP-"MCM;
Materials: metal, ceramics - "ceramics, plastics -" plastics;
Pin shape: long lead in-line - "short lead or leadless mounting -" spherical bumps;
Assembly method: through hole insertion - "surface assembly -" direct installation
There are many power supply packages for AC-DC converters, which meet the requirements of international standards and meet domestic requirements. This requires screening under general principles. Generally, when selecting a power module package, the following three aspects are required.
First, under certain power conditions, the smaller the volume, the better. In the process of packaging, the shrinking of the space means the expansion of the space, in order to provide more space to other parts of the system, to ensure the integrity of the function.
Second, when making package selection, you should try to choose products that meet international standards. Since the international standards are formulated and required for global manufacturers, the requirements are high and the compatibility performance is better. In addition, there are many manufacturers adopting this standard internationally, and there is a wider choice in the choice of supply, which will not cause limitations in the selection.
Third, we should focus on scalable products when making package selections for future system expansion and upgrades. On the basis of meeting international requirements, the currently widely used packaging mode is a half-brick, full-brick package. These two package modes are fully compatible with internationally renowned brands such as VICOR and LAMBDA. Under normal circumstances, the power range of international semi-brick products ranges from 50 to 200W, while the coverage of full brick products ranges from 100 to 300W, which can cover the requirements of domestic and most international products.
I believe that the two key factors in determining the package form are package efficiency and pin count. Why do you say this? First, the package efficiency refers to the ratio of chip area to package area to improve package efficiency. The principle is that the two are as close as possible to 1:1, and the package effect is the best. Secondly, the more pins, the higher the level, the more difficult the package process is. In principle, the pins should be as short as possible to reduce the delay, and the distance between the pins should be as far as possible to ensure mutual interference and improve performance. Of course, the thinner the better, based on the heat dissipation requirements.