How to choose the most popular electrical connecto

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How to choose electrical connectors

due to the continuous progress of technology and the need of market segmentation, the universal testing machine for metal materials shows a situation that the two series and four types of hydraulic and electronic Jinan assays are equal. Although the development trend of impact testing machine is to seek advanced technology, in the next period of time, affected by factors such as price, cost, manufacturing difficulty and so on, all kinds of testing machines will still compete and coexist in the market, only from the control characteristics Only by deeply understanding the advantages and disadvantages of the structure and important parameters can we choose a suitable product.

the complexity and speed of the computer have higher and higher requirements for the power distribution of the circuit board. Finishing pins provide a safe and powerful connection between printed boards (PCBs) and high-efficiency dc/dc converters used in current complex computer systems

finishing pins have been used in power converters, which have the following advantages

● its geometric crimping performance enables the discrete signal and power pins to be directly assembled into the plated through holes of the converter board

● after assembly, the pin shall undergo reflow welding in the surface mount process

● the shoulder of the pin defines the height of the converter and enables both sides of the converter to maintain air flow. Understanding the course content will be of great practical significance - Morris Town, New Jersey, USA - Honeywell (NYSE: HON) today announced that its spectrum shield bulletproof material was approved by reed composite solutions (RCS), a leading composite solutions provider It is adopted and used as a key ingredient in the bulletproof plate product Yitong recently launched by RCS

● pins can be machined from different copper alloys, and brass usually has good durability; Tellurium copper can now be used as a high current (more than 50a) pin

● power converter with relatively large through-hole welding (compared with SMT devices) another authorized SGPPL facility is located in Europe, which does not need screws and has better mechanical safety. Low power, pol and converter chips are more suitable for surface mount

● for system board designers, electroplated through holes simplify the internal power distribution

● for system engineers, "intrusive reflow" and other processes are suitable SMT processes, which can obtain the same reliability as wave soldering of through-hole components

● when wave soldering or reflow soldering is performed on the power converter, the shoulder of the pin can make the solder fill the electroplated through hole to avoid the occurrence of false soldering and other conditions affecting the current path

finishing pin

crimping pin with plated through hole

the thickness of copper plating on the through hole enables the crimping pin to be retained before wave soldering or reflow soldering. The size of the intersection in the geometric characteristics is the same as the aperture. Due to tool tolerances and losses, the hole diameter is usually 0.0005 inch smaller than the theoretical size of the drill

usually, the fine tip in the geometric characteristics is 0.002 inch, and it will not cut into the copper of the plated through hole when inserting. When the pin is pressed into the through hole, it is very important to leave a gap so that the solder can fill the through hole

when inserting the multi edge crimp pin into the through hole, the PCB assembly should give the actual drill size and general polishing hole tolerance (such as ± 0.002 inch, ± 0.003 inch, etc.)

if the copper plating thickness of the through hole is 0.001 ~ 0.0025 inches, the recommended minimum hole diameter is as follows

● triangle: minimum 0.023 inch (use 0.6mm drill bit)

● quadrilateral: minimum 0.039 inch (use 1.0mm drill bit)

● Pentagon: minimum 0.0605 inch (use 1.55mm drill bit)

● hexagon: minimum 0.0645 inch (use 1.65mm drill bit)

intrusive reflow soldering

intrusive reflow soldering, also known as "pin solder paste", is a welding technology that applies reflow soldering process to traditional through-hole components. The power converter is placed on the through hole of PCB, and reflow soldering is carried out like other SMT components. The solder will fill the electroplated through hole, making the reliability of the connection the same as that of wave soldering. (end)

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