Advanced Circuitry International

"Specializing in High-Tech RF / Microwave & Antenna PCB's"

Optimizing System PIM
At Advanced Circuitry International, we strive for 100% Repeatability and Consistency. Which is why we have a great track record keeping control of Passive Intermodulation (PIM) within our processes. 

We understand that our customers systems rely on very low levels of Passive Intermodulation and Minimal Interference. Testing for PIM usually requires Antenna evaluation at a cell site. By advanced processing and testing, carefully selecting materials, validated process controls, with proper design practices and understanding, excellent PIM can be consistently achieved.

“A number of factors affect PIM in the transmitting side of a base station. The presence of ferrous metals or other magnetic materials in the electromagnetic field near the antenna can significantly increase PIM.

Imperfect connections, such as conductive particles or chipped plating on the mating surfaces of conductors are a frequent cause. When designing and utilizing PCB antennas, it is important to remember PIM is not a basic laminate property. Just like insertion loss, gain, directivity, and many other important electrical variables, PIM is a system property that depends highly on the system design. However, our research has determined the laminate properties that can help contribute to low PIM variables.

Antenna designers know minimizing current density is key to achieving a low PIM system.

On the laminate side, we determined high conductor purity and low conductor profile, dielectric formulation and physical properties, as well as control of the conductor-dielectric interface can be controlled properly to minimize PIM generation.”

Factors to Optimize System PIM
Published: 02 August 2016
by Al Horn III

Optimizing System Signal Integrity
As we see more complex designs, the signal-integrity challenges are becoming more aware across all frequencies. In response, material selectors as well as material technologies are evolving. However, it can be difficult to find the sweet spot in where you’re not giving up signal integrity but are saving on material costs. With vast processing knowledge,our team at ACI can advise and prototype test materials according to your project specifications. 

The excerpt below does a great job explaining some key notes on Signal Integrity:
“The way materials are selected and used can help create products that really stand out against the competition by offering great performance and value. At a high level, choosing low-loss materials can ensure you meet signal-integrity targets, but can add cost to the end-product. On the other hand, if the design know-how is there, it may be possible to meet the same targets with a lower-cost material and remove the burden of those extra dollars from the BoM.

Typically, engineers will look at dissipation factor as their key parameter determining the impact the substrate material will have on signal integrity. It’s not the only relevant metric, however. At Ventec, we see the dielectric constant, or Dk, as having a large impact on the mechanical and electrical properties of the printed circuit board. For example, it can determine the overall Z height of the PCB, and this can affect the overall enclosure size and whether the electronic assembly will allow the finished product to meet the specified dimensions. Simply put, both the dissipation factor and the Dk describe the substrate’s energy-release properties, and the mathematics bears this out. The importance of the Dk, however, is often neglected.”

Seeking Material Gains – An Engineering Essential
Published: 26 October 2017
by Martin Cotton