Technical Library | 2020-03-09 10:50:17.0
A customer called the Helpline seeking advice for cleaning no-clean fluxes prior to applying a conformal coating. The customer's assemblies were manufactured with a no-clean rosin based solder paste (ROL0) and were cleaned with an isopropyl alcohol (IPA) wash. After cleaning, a white residue was sometimes found in areas with high paste concentrations and was interfering with the adhesion of the conformal coating (Figure 1). For conformal coatings to adhere properly, the printed circuit board (PCB) surface must be clean of fluxes and other residues. In addition, ionic contamination left by flux residues can lead to corrosion and dendrite growth, two common causes of electronic opens and shorts. Other residues can lead to unwanted impedance and physical interference with moving parts.
Technical Library | 2020-04-14 15:49:38.0
The number of through-hole components on printed circuit boards (PCB) has declined significantly over the last decade. Miniaturization in electronics has resulted in less THT (through-hole technology) and leads with a finer pitch. For this reason, the soldering of these components has also changed from wave soldering to Point-to-point selective soldering. Soldering these small, fine-pitch components is a challenge when surface mount components (SMD) are positioned very close to THT components on the PCB layout. This study, done in cooperation with a large automotive EMS customer, defines the process windows for through-hole technology for fine-pitch components. It determines what is feasible to solder and defines layout design parameter that make soldering possible with SMD areas and other components on the assembly.
Technical Library | 2020-05-08 18:22:31.0
A customer contacted the Helpline to perform analysis on a lead-free assembly which exhibited intermittent functionality. The lead-free assembly exhibiting intermittent functionality when pressure was applied to the ball grid array (BGA) packages. Industrial adaptation of a Restriction of Hazardous Substances (RoHS) compliant solder standard has created a new host of failure modes observed in lead-free assemblies. Pad cratering occurs when fractures propagate along the epoxy resin layer on the underside of the BGA connecting pads. While originating from process, design, and end use conditions, it is the combination of a rigid lead-free solder with inflexible printed circuit board (PCB) laminates that has advanced the prevalence of this condition. Pad cratering is simply the result of mechanical stress exceeding material limitations.
Technical Library | 2023-11-14 02:36:41.0
Understanding In-Circuit Testing (ICT) with PCBA ICT Testing Machine In-Circuit Testing, commonly known as ICT, stands as a sophisticated and precise method within electronics manufacturing. It serves to evaluate the functionality and integrity of individual electronic components on a Printed Circuit Board (PCB). The process employs specialized equipment called ICT Testers, meticulously designed to pinpoint defects, shorts, opens, and other potential issues within the PCB assembly. The Crucial Role of PCBA ICT Testing Machine 1. Quality Assurance ICT is pivotal in ensuring the overall quality and reliability of electronic products. Early identification and rectification of defects in the production process help manufacturers avoid costly recalls, rework, and post-production issues. 2. Cost-Efficiency ICT significantly reduces manufacturing costs by identifying defects at an early stage. This results in fewer defective units reaching the end of the production line, minimizing waste and rework. 3. Faster Time-to-Market Manufacturers can expedite the production process with ICT by swiftly identifying and resolving issues. This leads to faster product launches, providing a competitive edge in the market. Unveiling the Functions of PCBA ICT Testing Machine The ICT Tester, the core of the In-Circuit Testing process, conducts a battery of tests on each PCB, including: 1. Continuity Testing Checks for open circuits, ensuring all connections are properly established. 2. Component Verification Verifies the presence and orientation of components, ensuring alignment with the PCB design. 3. Functional Testing Some ICT Testers execute functional tests, assessing electronic components' performance as per specifications. 4. Short Testing Identifies unintended connections or shorts between different components on the PCB. 5. Insulation Testing Checks for isolation between different circuits, ensuring no undesired connections or paths. 6. Programming and Configuration In some cases, ICT Testers are used to program and configure specific components on the PCB. Advantages of PCBA ICT Testing Machine 1. High Precision ICT offers unparalleled accuracy in defect detection, making it crucial in modern electronics manufacturing. 2. Speed and Efficiency ICT Testers enable rapid testing, allowing manufacturers to assess a large number of PCBs in a short time. 3. Customization ICT Tests can be tailored to suit specific PCB requirements, ensuring thorough evaluation of every design aspect. 4. Data Collection ICT Testers gather valuable data for process optimization and quality control. In-Circuit Testing (ICT) is fundamental in electronics manufacturing, safeguarding product quality, reducing costs, and accelerating time-to-market. The ICT Tester, with its precision and efficiency, positions manufacturers at the forefront of the highly competitive electronics industry. Embracing ICT is not just a choice; it's a necessity for manufacturers striving for excellence in their products. I.C.T is a leading manufacturer of full SMT line machines in the electronic manufacturing industry. Discover how we can enhance product quality, boost performance, and reduce costs. Contact us at info@smt11.com for reliable global supply, unparalleled efficiency, and superior technical service.
Technical Library | 2015-08-27 15:32:16.0
Ever since there has been a widespread usage of surface mount parts, the trend of continued shrinkage of devices with ever finer pitches has continued to challenge PCB assemblers for the rework of same. Todays' pitches are commonly 0.5 to 0.4mm with packages of tiny outline sizes, 5 -10mm square, making the rework of such devices a challenge. In addition to the handling and inspection challenges comes the board density. Spacing to neighboring components continues to be compressed so the rework techniques should not damage neighboring components.
Technical Library | 2017-02-01 02:20:42.0
BGA Rework Course encompasses the skills necessary to perform rework of electronic printed circuit boards to include PBGA and CBGA technologies. There should be 'one-stop' solution, that offers a wide range of ball grid array rework and repair services.
Technical Library | 2016-10-06 15:13:02.0
One of the methods gaining in popularity for singulating rigid/flex, rigid and flex circuit boards post assembly is through the use of laser routing. This method has the advantage of speed, positional accuracy, no tooling wear and lastly no induced mechanical stresses on components during the singulating process.
Technical Library | 2007-02-01 09:27:47.0
The purpose of the testing was to compare the resistance and check for open circuit conditions of reworked BGA test samples made with and without StencilQuik™ after 500 thermal shock cycles. StencilQuick™ is a product of Best Inc. In this series of tests, the resistance of daisy chain resistance patterns running between the BGA and test board after exposure to thermal shock was measured.
Technical Library | 2024-01-08 18:36:01.0
The following aims lie behind the investigations described: The circuit board is an integrated structure made of metal and plastic. Like most integrated components enclosed in plastic, it absorbs water. When it is rapidly heated as, for example, in soldering technology temperature processes, it is a well known fact that the water will evaporate abruptly, leading to destruction. It is therefore essential that the circuit board be dried before these soldering processes. Circuit board manufacturers are extremely hesitant at providing instructions on drying their circuit boards. Information from the ZVEI [1] should also be regarded critically. The cardinal problem is the high temperature which is recommended for baking. If this is applied, the result is often de-lamination and distortion of the circuit boards. Corrosion and the formation of intermetallic phases of the metallic surfaces are also to be expected. The following investigates whether gentle drying at 45°C or 60°C and at low relative humidity achieves the same result as baking at high temperatures. The industry provides novel dry cabinets which are suitable for rapid drying at relative humidities below one percent.
Technical Library | 2024-01-08 18:44:00.0
Printed circuit boards, especially multilayer, flexible and rigid-flexible printed circuit boards, are extremely hygroscopic, i.e. they absorb and bind the moisture in the air. A dried polyimide film, for example, will have reached its moisture saturation level again after just a few hours.
Midwest Circuit Technology provides Carbide Router Bits and End Milling Cuters for use in PCB Depaneling equipment. We have over 35 years of supplying tools and machining experience in drilling, Routing, Test Fixture manufacture.
114 Barrington Town Square
Aurora, OH USA
Phone: 13309956900
