Сборка печатной платы со сквозным отверстием

Опубликовано 2020-07-06

Что такое сквозное отверстие (TH)?

Сквозное отверстие используется для соединения поверхностного слоя печатной платы и нижнего слоя траектории металлизации, используемой для вставки компонентов.

Что такое сквозная технология?

Технология вставки через отверстие, называемая технологией сквозного отверстия, представляет собой метод монтажа электронных компонентов. Включая использование выводов компонентов для вставки компонентов в существующие сквозные отверстия на печатной плате (PCB) и пайку электронных компонентов путем ручной сборки или автоматической вставки в загрузчик.

Автоматическая и ручная сборка сквозного отверстия

We use automatic through-hole placement technology for radial and axial components, preferably for small batch production. The layout of the automatic placement area aims to reduce material handling and labor. Our engineers use manual placement techniques to deal with compound through-hole assembly problems. Wave soldering is used for both surface mounting and through-hole components, but we prefer to use it for simple through-hole components. In a mixed technology board, the first board is wave soldered and then reflow soldered.

through-hole-pcb-assembly-01

Compared with surface mount technology, the through-hole mounting of components provides a strong mechanical bond and provides designers with more space for wiring. However, surface mount components can allow for more dense circuit configurations and utilize both sides of the circuit board. For larger and heavier components, through-hole installation is necessary because they require a stronger connection to be securely connected. Our dedicated team purchases components through authorized North American distributors to ensure that original authentic products are provided. The convenient availability of all necessary components allows us to provide fast manual, automated and combined through-hole assembly.

Our diligent staff ensures that they will not be affected by quality because they are trained to follow all inspection steps for small batch and prototype through-hole PCB assembly. We have a quality assurance team to monitor, check the process and support continuous process improvement. We currently use many advanced test equipment including AOI testing, visual inspection, online testing and optional functional testing to produce high-quality and cost-effective components.

History of Through-hole Technology

Through hole technology has almost completely replaced the earlier electronic product installation technology, such as point-to-point construction. From the second generation of computers in the 1950s until surface mount technology (SMT) became popular in the late 1980s, all electronic components on the usual printed circuit boards during the period were through-hole components. Printed circuit boards were printed with traces on one side at the earliest, followed by traces printed on both sides, and then multilayer circuit boards were also put into use. In order to be able to connect with a specific conductive layer, the through holes are developed into plated-through holes(ПТГ). В печатных платах SMT нет необходимости использовать плакированные сквозные отверстия для обеспечения взаимосвязи между компонентами схемы, но плакированные сквозные отверстия по-прежнему используются для достижения взаимосвязи между несколькими слоями. В настоящее время их чаще называют переходными отверстиями.

through-hole-pcb-assembly-02

Покрытые сквозные отверстия (PTH)

A printed circuit board (PCB) allows designers to create circuits using thin copper wires called copper wires, which are supported by the circuit board. PCBs are produced by routing one or more layers of copper to one or more layers of the substrate (usually FR-4 glass fiber), and then using acid to etch away excess copper. These traces can be connected from one layer of the PCB to another layer using copper-plated drill holes (called through holes). Most circuit boards seen on NightShade Electronics are 2 layers, but the PCB can be produced with copper traces of 1-20 layers or more. Many devices, such as smartphones or computer motherboards, have to find PCBs with a high number of layers in devices that have to propagate in small spaces.

Преимущество:

  • Manually assembling PTH components into a PCB is relatively simple, which makes it ideal for anyone making small circuit prototypes.
  • They can be used on breadboards without welding.
  • They are usually stronger than SMT components. This makes it ideal for connectors and rugged circuits.

Недостатки:

  • The work of assembling PTH components is relatively large. This makes them less suitable for mass production.
  • They are usually larger than SMT components, making them unsuitable for small circuits.
  • Due to the decline in popularity, many new chips are not available in PTH packages.

When Should I Use the PTH Component?

  • As long as physical strength is required, such as large connectors or large heavy components (transformers, inductors, large capacitors).
  • If the project is a hand-made prototype or small batch production.
  • Если вам нужно использовать макет для прототипирования.