A PCB or басма схемасы ал аркылуу электр тогу өткөндө жылуулукту пайда кылат. Туура изоляция болбосо, бул жылуулук PCBS үчүн олуттуу көйгөйлөрдү жаратышы мүмкүн.

Why do PCBS need insulation?

Before you can understand PCB insulation, you must understand: What is PCB?

PCBS, or printed circuit boards, are small green squares with copper sheets (but also in other colors). It can be found in almost any electronic device! Printed circuit boards enable electronic devices to function properly, making them a vital but invisible part of everyday life. Without them, computers, telephones, televisions and electronics would not work or exist.

Электр ПКБ үчүн абдан күчтүү. PCBS contain printed copper wires, so they naturally conduct electricity. Бирок, электрдик тетиктер өткөргүч эмес корпуста камтылбаса же өтө ысып кетсе, коркунуч жаратышы мүмкүн. ПХБ жездин коррозиясын болтурбоо жана өткөрүүчү материалдар менен кокусунан байланышты азайтуу үчүн изоляцияланышы керек. Proper insulation can help prevent the PCB from overheating or exploding.

There are several ways to isolate a PCB. There are several common insulation materials, but the exact type of insulation usually depends on the application of the PCB design.

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PCB insulating material

Common PCB insulation materials are usually formed as non-conductive substrates that can be fused together in multiple layers to allow current to flow correctly through the entire circuit board. Simpler PCBS can be single-sided or single-layer. Complex PCBS, such as those used for high-speed digital communications, may contain more than two dozen layers.

PCB insulation calculator can help you determine creepage distance and electrical clearance, which will be the determining factor in the exact type and quantity of insulation material. Creepage distance is the shortest distance between conductive parts, and clearance is the element separated by air rather than the substrate. Understanding creepage distance and electrical clearance is essential for calculating PCB insulation.

ПХБ өндүрүүчүлөрү изоляция үчүн ар кандай материалдарды колдонууну тандай алышат, FR-2 сыяктуу арзан пластмассадан алюминий сыяктуу бышык металлдарга чейин. The insulating material of a PCB usually determines its use. For example, the PCB in a cheaply made electronic toy would not need the same type of insulation as the PCB in a satellite.

ПХБ изоляциясын жана жылуулоо материалдарын жакшыраак түшүнүү үчүн, ПХБ изоляциясынын эң кеңири таралган беш түрүн изилдеп көрөлү.

FR-2

Fr-2 is a low grade flame retardant laminate option. It is made from a composite of paper and plasticized phenolic resin, making it light and durable. Single-sided circuit boards usually use this material. The FR-2 is halogen-free and hydrophobic and can be easily pressed or milled. The FR-2 is one of the cheapest options for PCB insulation and is a common choice for companies making disposable consumer electronics.

FR-4

Fr-4 is an advanced flame retardant laminate option. It is a composite material made of fiberglass woven fabric and is commonly used in the manufacture of double-sided and multi-layer PCBS. The FR-4 can withstand higher temperatures and physical pressures than the FR-2. It’s also an affordable material, making it a popular choice for manufacturers of high-end consumer electronics. The FR-4 is not machined fast, requiring milling, stamping or machined tungsten carbide tools.

Радио жыштыгы (rf)

RF substrates are designed to allow PCBS to operate in applications using high power RF and microwave. RF substrates are most commonly used for PCBS installed in military electronics, avionics and avionics. It is important to note, however, that some consumer electronics products contain this type of substrate. Кадимки RF субстратын түзгөн пластмассалар көп изоляцияны жаратпайт жана чоң агымдарды пайда кылуу милдетин жакшы аткарышат. RF жана микротолкундуу PCBS, адатта, бир же эки катмардан турат.

ийилме

Although most printed circuit boards are flat and rigid, there are some innovative PCBS that can bend in almost any direction without breaking. Flexible circuits require a similar but unique form of insulation. Flexible circuits are usually protected with A SPRAY of PCB insulation, in addition to plastic film is a popular choice. Flexible circuits require thin, strong PCB insulation coating so that they can move freely and fit in tight Spaces.

метал

The choice of metal as an insulator may seem strange. Metals are normally electrically conductive, and accidental conduction can cause a PCB to fail, catch fire or melt. However, in some cases, a PCB with a metal substrate may be more advantageous. Metal is an excellent conductor of heat and can withstand huge currents without breaking or burning. PCBS installed in electrically charged equipment that consumes a lot of power may require metal substrates to function effectively.

Industry influence

To prevent the PCB from overheating, catching fire, or catching fire, it must be adequately insulated. The type of insulation corresponds to the type of use provided by the PCB.

Жалпы максаттагы электрондук PCBS жөнөкөй жана үнөмдүү FR-2 же FR-4 субстраттары менен колдонууга ылайыктуу. RF субстраттары жогорку кубаттуулуктагы RFди камтыган тиркемелер үчүн көбүрөөк ылайыктуу.

Пластмасса сыяктуу ийкемдүү субстраттар ийкемдүү схемалардын жылуулоо талаптарын канааттандыруу үчүн ылайыктуу. Metals, on the other hand, are excellent conductors of heat while keeping the power electrons cool.