The high frequency of electronic equipment is a development trend, especially in the wireless network and satellite communication, the development of high speed and high frequency information products, and the standardization of voice, video and data used for large capacity and fast wireless transmission. Communication products. New generation products that need high frequency substrate.
Characteristics of high frequency PCB
- Impedance control is very strict, relative to line width control is very strict, the general tolerance is about 2%.
- The adhesion of PTH to copper is not high because of the special plate. Generally, plasma treatment equipment must be used to roughen the through-hole and surface to increase the adhesion of PTH hole copper and solder mask ink.
- Resistance welding can not be used before, otherwise the adhesion will be very poor, only micro etching water can be used for roughening.
- Most of the plates are made of PTFE. Ordinary milling cutter will form a lot of burr, so special milling cutter is needed.
- High frequency PCB is a special circuit board with high electromagnetic frequency. The frequency above can be defined as 1 GHz.
- Its physical properties, precision and technical parameters are very high, and it is often used in automotive anti-collision systems, satellite systems, radio systems and other fields.
- Generally speaking, the PCB industry believes that RF circuit board is any high frequency PCB working above 100MHz. In the RF level, Microwave PCB is used for 2GHz and above.
Use of high frequency laminates:
The laminates used to make RF printed circuit boards add a layer of security to all your equipment. These materials can help your device through three common types of heat transfer: conduction, convection, and radiation.
Thermal management is the primary concern for all PCB Applications in any industry, especially when high frequency is used.
To find the right high frequency laminate for your PCB, you need to discover various features and determine how to combine them into one picture. This is a complex puzzle, and you have to determine the trade-offs between multiple options and use cases.
You should select high frequency PCB laminates according to their adaptability to the application, and pay special attention to the following important features:
- Coefficient of thermal expansion (CTE)
- Dielectric constant and its thermal coefficient
- Copper / material surface profile smoother
- thermal conductivity
- Flexibility of conformal circuit