PCB (Printed Circuit Board)

A PCB (Printed Circuit Board) is the backbone of almost all modern electronic devices. It is a flat board made of an insulating material (such as fiberglass epoxy, called FR4) with a thin layer of conductive copper laminated on one or both sides.

Instead of using loose wires to connect components, a PCB uses copper tracks (traces) that are etched onto the board to create electrical connections between electronic components like resistors, capacitors, ICs, and connectors.

PCB Materials Comparison

FR-4 (Fiberglass Epoxy)

Pros:

• Low cost, widely available
• Good mechanical strength
• Flame resistant

Cons:

• Limited high-frequency performance
• Moderate thermal stability

Typical Applications: Consumer electronics, computers, industrial control

CEM-1 / CEM-3 (Composite Epoxy)

Pros:

• Cheaper than FR-4
• Easy to punch-process
• Good electrical insulation

Cons:

• Lower mechanical strength
• Less heat resistance

Typical Applications: Low-cost appliances, calculators, simple electronics

Polyimide

Pros:

• High thermal stability (Tg > 250°C)
• Flexible and durable
• Resistant to chemicals

Cons:

• More expensive than FR-4
• Higher moisture absorption

Typical Applications: Aerospace, automotive, flexible PCBs, medical devices

PTFE (Teflon)

Pros:

• Excellent dielectric properties
• Very low signal loss
• High-frequency suitability

Cons:

• Expensive
• Difficult to process (requires special handling)

Typical Applications: RF circuits, microwave boards, radar, 5G systems

Metal-Core (Aluminum, Copper)

Pros:

• Superior heat dissipation
• Good mechanical strength
• High current capacity

Cons:

• Heavier and less flexible
• Higher cost than FR-4

Typical Applications: LED lighting, power converters, automotive electronics

Flexible (Polyimide, Polyester film)

Pros:

• Can bend/fold
• Lightweight and space-saving
• High reliability in moving parts

Cons:

• Limited layer count
• More expensive manufacturing

Typical Applications: Smartphones, wearables, medical implants, cameras

Ceramic (Alumina, Aluminum Nitride)

Pros:

• Excellent heat conductivity
• Stable dielectric properties
• High durability

Cons:

• Very expensive
• Brittle and hard to manufacture

Typical Applications: Power electronics, military, aerospace, high-frequency devices