What you will learn:
- Properties of high frequency PCBs.
- Key Steps in High Frequency Printed Circuit Board Design.
- High frequency PCB applications.
High Frequency Printed Circuit Boards (PCBs) have become the lifeline of electronics manufacturing. These PCBs are known for their multiple functionality. Simply put, high frequency PCBs transmit electromagnetic waves with minimal loss. And they ensure high rate of signal flow. Some of the properties associated with high frequency PCBs include:
- Low dissipation factor: The dissipation factor of high frequency PCBs is between 0.0019 and 0.025. This ensures that the signal transmission rate is not affected and that there is minimal signal loss.
- Low dielectric constant: With a low and stable dielectric constant, these PCBs ensure smooth frequency transmission and minimal signal delay.
- Chemical resistance: The ability of high frequency PCBs to resist exposure to chemicals is of great value. It ensures that the panel does not corrode and can be used in environments where there is significant exposure to chemicals.
- Low moisture absorption: With a low water absorption rate, these PCBs are suitable for use in humid and humid environments.
- Low dimensional stability: High frequency PCBs are known to retain their size and not be affected by the temperature of the environment.
Due to these properties, their use is ubiquitous. However, PCB designers should ensure that the following steps are carefully followed when designing high frequency PCBs:
- Determine the frequency of the PCB signal: It is important to ensure that the voltage and power demands are established. Additionally, divide all power plans and determine if different signals can be supported. It is also important to ensure minimum tolerance levels and to determine how to reduce noise levels.
- Board stacking plan: The demands for the stacking layer must be planned. The specific material and its constraints must be understood.
- Planning: You need to divide the PCB into sections. In places that have digital and analog sections, proper isolation must be maintained to avoid interference.
- Power and mass planes: Once the PCB layout has been defined, the next step is to fully understand the ground plane. The division of the ground plane is imperative. You need to make sure that a resistor is included with the signal trace to improve the return path.
- Reduce the size of terrain models: High frequency PCBs often have small pads. Reducing the space minimizes stray capacitance and increases mechanical strength.
- Route frequency signals: High frequency signals are known to produce high radiation. By routing the frequency signals efficiently, you can avoid interference between the signals.
- Use the 3W rule: Using the 3W rule ensures that signal integrity is not compromised. This rule establishes that there is a difference between the traces and that the coupling effect is minimized.
- Apply the 20H rule: The coupling between ground planes and power planes can pose a threat to your design. With the 20H rule, you will ensure that the thickness between the adjacent power and ground planes is greater than the power plane.
Application of high frequency PCBs
The use of high frequency PCBs is more and more widespread. Some applications include:
- Communication systems in filter devices, amplifiers, booster stations and receivers.
- In the army for the production of ammunition and firearms.
- Radar systems that guide aircraft and prevent accidents.
- Critical diagnostic and monitoring devices in the medical industry.
High frequency PCBs are vital for the manufacture of electronic PCBs. Their robust characteristics make them the go-to device for electronic devices. In particular, they play a major role in high performance applications. With the increasing complexity of electronics and the need for faster signal transmission speeds, high frequency PCBs will only increase in importance.