Single ended impedance control: In this type, only a single trace is used to control the impedance in the PCB, and a reference ground layer is created based on these single ended traces.

Differential control impedance: In this type, there are two parallel line widths with a certain spacing to maintain the signal integrity of the PCB. In addition, only a reference layer was created for this section, or a fully grounded layer was designed. This basically depends on the PCB designer.

Coplanar control impedance: In this type, the single ended and differential ended traces have some defined planar spacing on the same impedance layer, and the impedance also requires a reference ground layer. It is suitable for both single ended and differential ends.

Usually, the impedance is controlled between 25 and 125 ohms, depending on its composition. PCB designers need to create high-frequency signals to meet the requirements of controlling impedance routing, and it also depends on the circuit board stack containing the material and its dielectric thickness. Therefore, the following are some components required to define control impedance:

Circuit board thickness and line width

The materials and values of core materials and prepreg

Define the dielectric constant of the core material and prepreg of the material

Reference grounding layer (basically, this means that controlling impedance routing requires some reference grounding layer)

Do you need solder resist.

Frequency and temperature: Control impedance to be low at very high frequencies, and due to high temperatures, control impedance will undergo thermal expansion. （ /- 150 ppm）

Tolerance: The impedance control is set based on manufacturing tolerances. Impedance control typically uses a tolerance of/-10%. But sometimes manufacturers allocate smaller tolerances to control impedance. This is why it affects impedance.

Reference Ground: The reference ground layer in the impedance control PCB needs to control the impedance routing to meet the requirements. Sometimes designers create partial grounding. Therefore, due to the presence of the inguinal plane, it also affects the control impedance.

Routing: Sometimes, due to wiring issues, designers may reduce the spacing between the inner and outer copper layers.

Dielectric material and thickness: Manufacturers set up stacks to match circuit board thickness and control impedance, but they choose higher materials and thicknesses of dielectric. Therefore, it is 100% affected by the control impedance.

Many PCB operations are indeed impedance controlled in order to achieve faster processing speeds and improve PCB performance with less energy. For a long time, many PCB manufacturing companies have been researching impedance control to improve PCB performance. The following are the advantages of impedance controlled PCB.

Provide reliability: It provides reliability, allowing for faster processing and improved PCB performance with less energy consumption.

Provide better energy reflection in high pulses: Control impedance PCB to provide better energy reflection in high pulses without causing any interference to energy reflux.

Improving signal integrity: Many companies use impedance control of RF circuits to enhance signal integrity and performance.

Effective management of electromagnetic interference: We can also manage electromagnetic interference by controlling impedance.

There are many software programs in the PCB industry. In addition, some companies also have their own impedance calculation software.

Special impedance control calculator software: The control impedance calculation mainly uses Smith chart and polar coordinate grid. Therefore, this software helps to calculate the control impedance in PCB by selecting different dielectric cells and pre impregnated materials, and we can easily stack them as needed. Polar coordinate instruments and calculators are widely used.

Online impedance control calculator: Many websites and manufacturing companies provide facilities for online calculation and control of impedance. Therefore, this is the best way to obtain a solution in a short and simple manner.

Incorrect layer information: Sometimes designers mistakenly add layer information to PCB impedance control. When you use PCB impedance control to make dense circuit boards, this is a major mistake. Therefore, please ensure that the PCB impedance control values, reference grounding, and control impedance layer information are correctly filled in the stacking and manufacturing documents. DFM engineers can easily ensure that they understand the correct information about the artwork.

Incompatible wiring width: Sometimes, many customers design multiple control impedance wiring, but design multiple wiring in the same layer, which does not meet the requirements for designing control impedance wiring in the same layer. Then, due to certain reasons, such as the control impedance ohm not having a precisely defined value, the control impedance cannot function properly.

Control impedance tolerance: Most PCB manufacturers use a 10% tolerance to control impedance. Sometimes customers allocate lower tolerances to achieve impedance control. But this will only affect control

Impedance on closely spaced PCBs and high-density circuit boards. If this type of

If an error occurs, the manufacturing department will stop working and inquire

By providing accurate clarification, customers can gain more tolerance.

High frequency operation

RF applications

100 MHz signal processing and control

If pursuing cost-effective FPC manufacturing services, choosing a Chinese manufacturer is the best choice. As a manufacturing powerhouse, China has abundant resources, cheap labor, and a large number of technical personnel. We recommend Haibo, a Chinese FPC assembly service provider with over 10 years of experience, who has performed outstandingly in various aspects

Efficient and reasonable quotation:There is an efficient quotation process to assist you in making decisions, providing reasonable prices and highly competitive quotes in China.
High quality and reliable products:Produce high standard printed circuit boards, manufacture and test according to specifications, international standards, and internal controls, and conduct pre production inspections to ensure robust processes.
Quick and on-time delivery:The assembly equipment is in good condition, with high productivity, minimal downtime, short delivery time, and also provides urgent services.
Timely and effective response:Always respond to customer needs, provide accurate information, answer questions through multiple channels, and offer one-stop services.
Strong technical strength:China's FPC manufacturing technology is leading, and Haibo has a complete SMT solution that covers assembly, inspection, and other capabilities. It also provides prototype production and customization services.