Encapsulant solutions are commonly used to enhance protection of circuit boards from environmental and liquid contaminants, chemical attack, and electrical shortages. While potting materials provide many positive attributes when used to protect PCBs, sometimes other issues arise during and post application of these compounds. This blog focuses on “bubbles” forming within the encapsulant itself.
Topics: Humiseal, Encapsulants
IPC CC-830 revision B is a conformal coating qualification standard mostly used by board fabricators, OEM design engineers, and coatings suppliers.
There are two fundamental uses of this IPC standard:
In this blog, we will go over some of the specifications along with tests requirements, passing criteria, and quality characteristics.
Topics: Conformal Coatings, Conformal Coating Process, Standard Qualifications, IPC-CC-830B
The conformal coating process, like any other processes, has different variables, inputs, and outputs. In order to be able to control the results of your application (outputs), we need to fully understand how each variable affects the process.
The importance of the variables
To get the right amount of liquid, thickness, right coverage, no contamination on keep out areas, etc., you need to identify and understand the variables of the process.
The most important variables:
In this blog, we will concentrate on reviewing the first variable: Viscosity
Topics: Conformal Coatings, conformal coating application, viscosity
Electronics continue to be placed into harsher environments, and PCB component vibration dampening remains a challenge for many industries. When the solder connection strength is not going to be sufficient to withstand years of vibration, there is a solution: staking materials.
Numerous fields of industry manufacture products that are prone to high-vibration environments. Some of them are:
Topics: Adhesive Solutions, Vibration Suppression
Have you ever seen your conformal coating separate or de-wet? Have you observed the conformal coating to flake off after cure? The key to your success is understanding the relationship between surface energy (of the substrate) and surface tension (of the conformal coating). There are some simple steps you can take to help ensure you possess a healthy balance of both.
Topics: Humiseal, Conformal Coating Process, proper wetting, troubleshooting, surface energy, conformal coating application
The application of the conformal coating in a uniform and consistent coverage is a key challenge that defines the reliability of the finished product.
A thin coating will provide inadequate protection against corrosion or insulation between conductors. Conversely, if the conformal coating is too thick, it will increase the risk of forming other types of coating defects such as bubbles, insufficient curing, and potential cracking during thermal shock cycles.
Besides the verification of the process parameters such as coating viscosity and the application method is correctly setup, the amount of conformal coating material applied on the printed circuit boards can be measured before curing. For this, wet film conformal coating thickness gauges are used. This method ensures quality control while the coating material is still wet.
Topics: Conformal Coatings, Coating Application Preparation, Conformal Coating Process
One of the basic components used in most automatic or semi-automatic conformal coating processes is compressed air. Pressurized air moves the liquid coating from the tank, through the hoses and the valves onto the PCB. Since the pressurized air makes direct contact with the conformal coating, there are critical properties that must be taken into consideration, especially with moisture sensitive materials. What critical factors are important when working with UV40, UV500, 1A20 or any RTV Silicone from HumiSeal?
ENERGY STAR, The United States Environmental Protection Agency program that provides certification to buildings and consumer products which meet certain standards of energy efficiency, defines what a LED light is.
LEDs, or light-emitting diodes, are semiconductor devices that produce visible light when an electrical current passed through them. LEDs are a type of Solid State Lighting (SSL), as are organic light–emitting diodes (OLEDs) and light–emitting polymers (LEPs).
Also states: Thermal management is probably the single most important factor in the successful performance of a LED product over its lifetime because the higher the temperature at which the LEDs are operated, the more quickly the light will degrade, and the shorter the useful life will be.
Topics: Blog, LED technology, Conformal Coatings
How do you select and test a conformal coating that is right for your specific application? Or maybe you would like to create your own test specification due to any special characteristics of your device’s operating environment? Or depending on your geographical location, you may also be required to use a different testing specification that is dictated by local authorities.
A widely used method to create an internal specification, is to simply select a conformal coating material that meets an existing specification standard. Such standard could be MIL-I-46058C or IEC-60664. However, you must be careful to ensure that the existing standard that you choose, does indeed meet 100% of your requirements. In such cases, you may have to specify test methods from other existing standards.
Topics: conformal coating, testing procedure
So, you’ve spent a considerable amount of time setting up your conformal coating process only to observe the dreaded cobwebbing effect once you start applying the material. Well, in this blog post, I’m going to run through the common root causes and provide some simple solutions you can take to get you back to applying your coating in a defect free manner.
