Microwave Tech - High frequency microwave sheet

High frequency microwave sheet

Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. In the development trend of market economy and high-tech content products, Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. An additional branch is high-frequency microwave printed boards and metal-based printed boards.

1. The high-frequency microwave printed circuit board is heating up on the land of China. In recent years, in East China, North China, and the Pearl River Delta, many printed board companies have been staring at the high-frequency microwave board market. They are gathering together high-frequency waves, Teflon (PTFE) dynamics and information, Regarding such new types of printed boards as a set of products necessary for the electronic information high-tech science and technology industry, the investigation, research, and research and development are emphasized. The CEO of a company definitely believes that the high-frequency microwave board is a new economic improvement point for the company in the future. Senior overseas experts predict in advance that the market for high-frequency microwave panels will progress rapidly. In the fields of communications, medical care, military, transportation, computers, spectrographs, etc., the demand for high-frequency microwave panels is rapidly rising. High-frequency microwave boards account for about 15% of the world's total printed boards. Many PCB companies in Taiwan, South Korea, Europe, the United States, and Japan have made plans to progress in this direction. European and American high-frequency microwave sheet suppliers Rogers, Arlon, Taconic, Metclad (NELCO), GIL Toyo Chukoh (Zhongxing Chemicals) have entered the potential market of China since 2007, looking for theories, explaining and imparting related technologies. European and American sheet metal suppliers have been able to supply more than 100 varieties of dielectric constants ranging from 2.10, 2.15, 2.17, ... to 10, and even higher sheet series. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd. In Pearl River Delta Studies and Yangtze River Delta Studies, it is reported that many companies have placed bulk orders for Teflon and high-frequency boards. . Many domestic radar and communications research institutes printed circuit boards require high-frequency microwave sheets to increase year by year. Domestic companies such as Huawei, Bell, and Wuhan Institute of Posts and Telecommunications need more and more high-frequency microwave printed boards year by year, and overseas companies engaged in high-frequency microwave products have also moved to China to collect and purchase high-frequency microwave printed boards nearby. plate. (What is high frequency? Above 300MHZ, that is, the shortwave frequency range with a wavelength of more than 1 meter, generally called high frequency.)

2. Why does it heat up? There are three reasons.

(1) The local frequency bands of high-frequency communication originally used in military fields were given to people's lives (started in 1996), which greatly improved the high-frequency communication used in people's lives. It has a grand vision in various fields such as long-distance high-speed communication, navigation, medical treatment, transportation, transportation, and inventory.

(2) High confidentiality, high transmission quality, mobile phones, transportation phones, and wireless communications are progressing to high frequency, and high screen quality enables broadcast and television transmission, and VHF and UHF broadcast programs. High-volume information transmission requires satellite communications, microwave communications and optical fiber communications to be high-frequency.

(3) The experience of computer technology processing has increased, and the volume of information memory has increased. Therefore, it is necessary to require high-speed signal transmission. In short, the high frequency and high speed of electronic information products put forward high requirements on the special high frequency properties of printed boards. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.

3. Why is the printed board required to have a low εr (Dk)? εr or Dk, called the dielectric constant, is the ratio of the capacitance between the electrodes when they are charged with something and the capacitance of a vacuum capacitor of the same construction. Generally express the experience volume of a certain material to store electrical energy. When the εr is large, the experience of storing electric energy is large, and the transmission speed of the electric shock signal of the circuit will be reduced. The current direction of the electrical signal passing through the printed board is generally positive and negative alternately, which is equivalent to the process of continuously charging and discharging the substrate. In the mutual exchange, the electric volume will affect the transmission speed of the evangelism. And this kind of influence is even more critical in high-speed transmission devices. εr low expression storage experience is small, the charge and discharge process is fast, so the transmission speed is also fast. Therefore, in high-frequency transmission, a low dielectric constant is required. There is an additional concept that is media damage. Under the effect of the alternating electric field, the energy consumed by the electric media material due to heat + ray is called the media loss, which is generally expressed by the media loss factor tanδ (deta). ε and tanδ are proportional, and high-frequency circuits also require low ε, and the medium damage consumption tanδ is small, so that it can + the damage consumption is also small. Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.

4. The ε of PTFE (Teflon) printed boards. Among the substrates of printed boards, the dielectric constant ε of PTFE is the lowest, typically only 2.6~2.7, while ordinary glass cloth epoxy The dielectric constant ε of FR4 of natural resin base material is 4.6~5.0. Because of this, the signal transmission speed of Teflon printed board is much faster than FR4 (about 40%). Teflon board has an intermediate damage factor of 0.002, which is 10 times lower than FR4's 0.02, and energy + ray damage is also much smaller. In addition, PTFE is called the "molecular compound plastic king". It has good electrical insulation, chemical and thermal stability (until now there is no solvent that can dissolve it below 300 degree Celsius), Therefore, high-frequency and high-speed signal transmission must first use Teflon or other dielectric constants.