A PCB or bwrdd cylched printiedig yn cynhyrchu gwres pan fydd cerrynt trydan yn llifo trwyddo. Heb inswleiddio priodol, gall y gwres hwn achosi problemau difrifol i PCBS.

Pam mae angen inswleiddio PCBS?

Cyn y gallwch ddeall inswleiddio PCB, rhaid i chi ddeall: Beth yw 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.

Mae trydanol yn bwerus iawn ar gyfer PCB. PCBS contain printed copper wires, so they naturally conduct electricity. Fodd bynnag, gall cydrannau trydanol fod yn berygl os nad ydyn nhw wedi’u hamgáu mewn tŷ an-ddargludol neu’n mynd yn rhy boeth. Rhaid inswleiddio’r PCB i atal cyrydiad copr a lleihau cyswllt damweiniol â deunyddiau dargludol. 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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Deunydd inswleiddio PCB

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. Gall PCBS symlach fod yn unochrog neu’n un haen. 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.

Gall gweithgynhyrchwyr PCB ddewis defnyddio amrywiaeth o wahanol ddefnyddiau ar gyfer inswleiddio, o blastig rhad fel FR-2 i fetelau garw fel alwminiwm. 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.

Er mwyn deall deunyddiau inswleiddio ac inswleiddio PCB yn well, gadewch i ni archwilio’r pum math mwyaf cyffredin o inswleiddio PCB.

FR-2

Mae Fr-2 yn opsiwn lamineiddio gwrth-fflam gradd isel. It is made from a composite of paper and plasticized phenolic resin, making it light and durable. Mae byrddau cylched un ochr fel arfer yn defnyddio’r deunydd hwn. Mae’r FR-2 yn rhydd o halogen a hydroffobig a gellir ei wasgu neu ei falu’n hawdd. 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.

Amledd radio (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. Nid yw’r plastigau sy’n ffurfio swbstrad RF nodweddiadol yn cynhyrchu llawer o inswleiddio ac yn perfformio’n dda ar gyfer y dasg o gynhyrchu ceryntau mawr. Fel rheol, dim ond un neu ddwy haen sydd gan PCBS RF a microdon.

hyblyg

Er bod y mwyafrif o fyrddau cylched printiedig yn wastad ac yn anhyblyg, mae yna rai PCBS arloesol a all blygu i bron unrhyw gyfeiriad heb dorri. 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.

metel

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. Mae metel yn ddargludydd gwres rhagorol a gall wrthsefyll ceryntau enfawr heb dorri na llosgi. PCBS installed in electrically charged equipment that consumes a lot of power may require metal substrates to function effectively.

Dylanwad diwydiant

Er mwyn atal y PCB rhag gorboethi, dal tân, neu fynd ar dân, rhaid ei insiwleiddio’n ddigonol. The type of insulation corresponds to the type of use provided by the PCB.

Mae PCBS electronig pwrpas cyffredinol yn addas i’w ddefnyddio gyda swbstradau FR-2 neu FR-4 symlach a mwy cost-effeithiol. Mae swbstradau RF yn fwy addas ar gyfer cymwysiadau sy’n cynnwys RF pŵer uchel.

Mae swbstradau hyblyg fel plastigau yn addas iawn i fodloni gofynion inswleiddio byrddau cylched hyblyg. Metals, on the other hand, are excellent conductors of heat while keeping the power electrons cool.