Testing and components after PCBA cleaning

Testing and components after PCBA cleaning
Let's discuss which tests need to be carried out after the professional training is completed The inspection after PCBA cleaning is mainly carried out through visual inspection For high reliability products, special test equipment and standard methods are required to measure cleanliness The measurement standards of cleanliness mainly include ion contamination and surface insulation resistance
1. Cleaning standard
1. Ion pollution At present, there is no clear ion pollution standard for polychlorinated biphenyl processing plants. It usually refers to MIL2.809 or ANSI/J-001B.
2. Surface insulation resistance (SIR) is usually measured by comb circuit. This method is intuitionistic, quantifiable, and has high reliability, but it is also the most difficult, which requires comb circuit for measurement. The surface insulation resistance SIR – 10 to 10/power is usually required.
2. Inspection method of professional PCBA processing plant
The inspection of the cleaning process shall be carried out according to the cleaning requirements of the product.
For military products, medical products, precision instruments and other products with special requirements, omega (Î) meters and other measuring instruments shall be used to measure the degree of staining of sodium ions. In addition, shape test pieces are usually used to test surface insulation resistance.
The cleanliness of Omega (Î ©)  Meter is measured by immigrating the printed circuit board (PCBA) in a clean standard solvent Provide the equivalent sodium ion content of the cleanliness index of the tested part The required products can be visually inspected
The visual inspection method requires the use of a 4x microscope. The surfaces of PCB and components shall be clean and free of beads, flux residues and other contaminants, and the criteria for observing contaminants shall be determined.

Development Prospect of PCBA Components
With the development of PCBA module R&D technology, the module is developing towards smaller size and higher integration. The packaging of the module is also developing towards smaller size, lighter weight, higher working frequency, and towards strong anti-interference ability and high reliability to meet the requirements of assembly products.
Modularization is the development direction of future components. With the increasingly limited size of components, the precision of automatic production equipment of professional PCBA processing plants is approaching the limit, and the compounding and modularization of chip components will be rapidly developed and widely used.
The main function of PCBA printer is to paint solder paste on the designated bonding pad of PCB. According to the degree of automation, printing presses can be divided into manual printing presses, semi-automatic printing presses and full-automatic printing presses.
Various parameters and actions of the manual printer need to be adjusted and controlled manually, which is usually used for small batch production or low difficulty products; In the clamping process of the semi-automatic printer, except for manually placing the printed circuit board, other actions are automatically completed by the machine. However, the position alignment of the first printed circuit board and the template window is manually realized; Automatic printers are usually equipped with high-precision optical mid systems for large-scale production in professional PCBA processing plants.
The starting operation of the printing machine in the professional PCBA processing plant is basically the same. The Digital Signal Processor-1008 automatic printer consists of a rack, a printing stand, a template fixing mechanism, a print head system and other options (charge coupled device, positioning system, wiper system, 2D and 3D measurement system, etc.). Equipped to ensure printing accuracy.
Professional PCBA processing plants should ensure that all employees pay attention to electrostatic protection during the production process, so as to truly implement the electrostatic protection system project, eliminate electrostatic hazards, ensure production safety, and improve product quality and reliability