High frequency PCB manufacturing can be used when special signal requirements is needed for electronic equipment and products. The frequency range of 500MHz – 2GHz is its operation environment. Hence, these are ideal for high-end applications. Today, the complexity of electronic devices is rapidly increasing. Hence, we need high frequency PCB for providing faster signal flow rates.
1. These typically have a low dielectric constant (approximately 2.40) and have tight tolerances.
2. They feature a small dissipation factor. Hence, they have a low loss tangent. Therefore, it allows for faster signal propagation and low signal distortion. So, they are suited for high frequency applications that demand high reliability.
3. These have a thermally stable structure because they have a relatively low Z-axis CTE. So, the low CAF resistance and the low Z-CTE leads to a long lifespan for these PCBs.
4. They feature excellent dimensional stability. Hence, ideal for applications involving extreme environmental conditions.
5. These feature small moisture absorption. Hence, they provide excellent resistance against heat and moisture.
6. They have ideal properties for reflow conditions. Hence, they are favorable for industrial application.
In the PCB industry, people often confuse the term high speed PCB layout with high frequency PCB layout. They do this because they think that the two terms are the same. However, that is not the case because the meaning of these two terms is completely different.
High Speed PCB design relates to PCB which have to allow for transmitting data at a very high rate. Hence, it refers to the time domain.
High Frequency PCB design relates to PCB which deals with signals having high frequency and shorter wavelengths. Hence, it refers to the electromagnetic waves of the incoming and outgoing signals.
Since High Frequency PCB layout operates on high frequency therefore, they are often subjected to extreme heat. If the material is not suitable then it may lead to the accumulation of thermal stresses. Hence, we need to select such a material that offers a favorable Coefficient of Thermal Expansion (CTE). Apart from this, the material should have high dimensional stability. So that it doesn’t degrade while operating.
The following chart will help you in selecting high frequency PCB materials.
| Material | Dielectric Constant | Dissipation Factor | Lamination Temperature (oF) | Re-melt Temperature (oF) |
|---|---|---|---|---|
| FEP | 2.10 | 0.0010 | 565 | 520 |
| PTFE | 3.00 | 0.0013 | 700 | 640 |
| LCP | 2.90 | 0.0025 | 554 | 520 |
| Thermoset Hydrocarbon | 3.90 | 0.0040 | 350 | N/A |
| FR-4 | 4.50 | 0.0180 | 360 | N/A |
We use high frequency PCB in almost every industry. However, we also interact with them in our daily lives. You can observe a high frequency PCB in the ATM machine of a bank, a vending machine, the computer you are using to read this, the mobile phone you use to browse the internet, and the Wi-Fi router in your homes or offices.
Some of the prominent industrial domains which rely on high frequency PCB are,
Different schools of thoughts have different approach to this question. However, there is no specific definition that tells you when to go with high speed design. So, it mainly depends on your specific circumstances. However, we have put together the following high frequency PCB design guideline for you so that you can easily make this decision.
The following rule of thumb will serve as a broad guide for you. So, you should remember that,
“You should look towards high speed design whenever the trace length becomes a significant fraction of the fastest signal’s wavelength.”
This implies that PCBs which are large in size require high speed design solutions at significantly lower frequencies. However, PCBs which are smaller in size require high speed design solutions at relatively higher frequencies. The difference between the two is due to the difference in trace lengths.
MOKO Technology is a renowned name in the PCB industry and we have years of experience since 2006. We specialize in the design and development of customized High Frequency PCB as per your needs. We have a sophisticated setup and have the necessary standard certifications. If you require your PCBs to give excellent performance then you should discuss your high frequency PCB project with us today.