Advanced PCB vs standard PCB: Differences in features, applications, and manufacturing processes

Circuit boards, also known as printed circuit boards (PCBs), or FPC circuit boards (also called flexible circuit boards), are highly reliable and flexible printed circuit boards made from polyimide or polyester films.

 

Circuit boards, also known as printed circuit boards (PCBs), or FPC circuit boards (also called flexible circuit boards), are highly reliable and flexible printed circuit boards made from polyimide or polyester films. Types of circuit boards include ceramic circuit boards, aluminum oxide ceramic circuit boards, aluminum nitride ceramic circuit boards, aluminum substrates, high-frequency boards, thick copper boards, impedance boards, ultra-thin PCBs, and printed (copper etching technology) circuit boards.

PCBs are widely used not only in the electronics industry but also in medical fields and satellite telecommunication sectors of military equipment. Here, we will provide an overview of advanced PCBs and standard PCBs, detailing their relationships and distinctive characteristics.

What is an advanced PCB?

An advanced PCB refers to a circuit board with higher requirements for signal transmission speed, frequency, and data throughput. Its design and manufacturing processes demand additional considerations, such as signal integrity, electromagnetic compatibility, and thermal management, ensuring stable and reliable operation under various complex conditions.

What is a standard PCB?

A standard PCB achieves electrical connections and functional integration between electronic components through a combination of conductive and insulating materials. Typically composed of conductive layers (such as copper) and insulating layers (such as epoxy resin or fiberglass), it features fixed parameters for size, layout, line width, and spacing. These parameters adhere to industry standards and specifications to ensure the reliability and stability of the circuit board.

What are the types of advanced PCB?

Advanced boards go beyond traditional single or double-sided PCBs, incorporating specialized features, materials, and manufacturing processes to meet the demands of modern electronic applications. Here are various types of advanced PCBs:

Multilayer PCBs: These boards consist of multiple layers of conductive material separated by insulating layers (substrates). They offer increased routing density, better signal integrity, and enhanced functionality due to the ability to accommodate more complex circuits and components.

High-Density Interconnect (HDI) PCBs: HDI PCBs utilize microvias, buried vias, and finer line and space features to achieve higher routing density and smaller form factors. They’re crucial for compact and high-performance devices, enabling miniaturization without compromising functionality.

Flexible PCBs: Flex PCBs use flexible substrate materials that allow the board to bend or flex during use. They are ideal for applications requiring compact, lightweight, or curved designs, such as wearables, medical devices, and aerospace systems.

Rigid-Flex PCBs: Rigid-flex boards combine rigid and flexible substrates, offering both mechanical support and flexibility. They are suitable for applications where a combination of rigid and flexible designs is necessary, providing reliability in complex form factors.

Embedded Component PCBs: These PCBs integrate passive and active components within the substrate, eliminating the need for discrete components. They enhance miniaturization, reduce assembly complexity, and improve performance.

RF/Microwave PCBs: Designed for high-frequency applications, RF and microwave PCBs utilize specialized materials and design techniques to maintain signal integrity, reduce interference, and handle high-frequency signals without loss.

Metal Core PCBs (MCPCBs): MCPCBs have a metal core (usually aluminum or copper) for enhanced thermal conductivity. They efficiently dissipate heat, making them suitable for high-power LED lighting, power supplies, and automotive applications.

Backplane PCBs: Backplanes serve as the backbone of complex systems, providing connectivity between multiple PCBs or electronic modules. They often feature high-speed connectors and signal routing capabilities for data-intensive applications.

High-Temperature PCBs: These boards use materials capable of withstanding elevated temperatures without compromising performance. They find applications in automotive, aerospace, and industrial environments with harsh operating conditions.

Hybrid PCBs: Hybrid PCBs combine different materials and technologies, such as combining rigid and flex portions or incorporating ceramic substrates alongside traditional materials, to meet specific application requirements.

Each type of advanced PCB caters to specific design considerations, industry demands, and technological requirements, offering unique features and capabilities to support the development of innovative and high-performance electronic devices across various sectors.

Differences Between Advanced PCBs and Standard PCBs

Advanced PCBs and standard PCBs exhibit significant differences in design principles, material selection, manufacturing processes, performance characteristics, and application fields. Below is a detailed comparison of these two types of PCBs:

1. Design Principles

Signal Integrity

• Advanced PCB: Special emphasis on signal integrity to ensure stability and accuracy during signal transmission. This involves advanced routing techniques like differential pair routing, length matching, and impedance matching.
• Standard PCB: Focuses mainly on functional implementation with relatively low requirements for signal integrity.

Electromagnetic Compatibility (EMC)

• Advanced PCB: Addresses EMC to minimize electromagnetic interference (EMI) and radio frequency interference (RFI), often through shielding, ground vias, and other measures.
• Standard PCB: Has simpler designs with less emphasis on EMC.

Power Integrity

• Advanced PCB: Requires attention to power integrity to ensure stable and reliable power delivery.
• Standard PCB: Relatively lower demands for power integrity.

Thermal Management

• Advanced PCB: Prioritizes thermal management to ensure stability and reliability in high-temperature environments. May use thermal conductive materials such as thermal adhesives and pads.
• Standard PCB: Lower thermal management requirements, usually without special measures.

2. Material Selection

Substrate Materials

• Advanced PCB: Uses high-performance materials like FR-4 (glass fiber-reinforced epoxy), Rogers, and PTFE (polytetrafluoroethylene), which have low dielectric constants (Dk) and dissipation factors (Df) to enhance signal speed and reduce loss.
• Standard PCB: Utilizes cost-effective materials like FR-2 and FR-3.

Copper Foil

• Advanced PCB: Employs thicker copper foil to increase current-carrying capacity and reduce resistance.
• Standard PCB: Uses thinner copper foil to minimize costs.

3. Manufacturing Processes

Routing

• Advanced PCB: Requires adherence to specific rules, such as differential pair routing and length matching, to ensure stable and accurate signal transmission.
• Standard PCB: Primarily focuses on functional routing with fewer restrictions.

Impedance Control

• Advanced PCB: Enforces strict impedance control, considering materials and routing design to ensure signal stability.
• Standard PCB: Impedance control requirements are minimal.

Blind/Buried Vias

• Advanced PCB: Often incorporates blind and buried vias to facilitate interlayer connections.
• Standard PCB: Rarely uses blind or buried vias.

Surface Treatment

• Advanced PCB: Typically uses advanced treatments like ENIG (Electroless Nickel Immersion Gold) for improved signal transmission and oxidation resistance.
• Standard PCB: Commonly uses HASL (Hot Air Solder Leveling).

Specific comparison

ITEMS APPLICATION	Advanced PCB	Standard PCB
Production	individual working panel	mixed working panel
Quantity	≥1 piece	5,10,15,20,25…pieces
Drilling	Min Mechanical Hole Size 0.15mm,Laser hole 0.1mm	Min Mechanical Hole Size 0.2mm
Plating	PTH (Hole copper thickness≥20um),IPC 3(25um)	PTH（Hole copper thickness≥18um）
Soldermask offset	±2mil	±3mil
Dimensional deviation	±0.13mm	±0.2mm
Warping angle	0.75%	1%
Test method	A.O.I,Kelvin Four-terminal sensing,Microsection Inspection,Solderability Test,Impedance Test…	A.O.I.,Fly Probe Testing
Glass transition ℃	>140℃	>130℃
Package	Humidity indicator cards	None
Inspection report	Inspection report	None
Standard	IPC Class 2,IPC Class 3,Automotive Standard, Customer Standard	IPC Class 2
Etched line	Forbid to repair tracks(IPC 3,Automotive, Customer Standard)
Cleanliness	Cleanliness requirements beyond those of IPC	Meet IPC standards
Certification	UL,ISO9001:2008,ISO14001:2004,ISO/TS16949:2009, RoHS etc.	UL,ISO9001:2015,RoHS etc.

4. Performance Characteristics

Signal Transmission Speed

• Advanced PCB: Delivers higher transmission speeds, suitable for high-speed data transfer.
• Standard PCB: Lower transmission speeds.

Signal Loss

• Advanced PCB: Lower signal loss, enhancing stability and accuracy.
• Standard PCB: Higher signal loss.

Electromagnetic Compatibility

• Advanced PCB: Better EMC, effectively reducing EMI and RFI.
• Standard PCB: Inferior EMC performance.

Thermal Performance

• Advanced PCB: Superior thermal performance for stable operation in high-temperature environments.
• Standard PCB: Less effective thermal performance.

5. Application Fields

Advanced PCB: Widely used in high-speed data transfer, high-speed communication, high-performance computing, aerospace, and military sectors. These fields demand superior signal transmission speed, EMC, and thermal performance.

Standard PCB: Commonly found in consumer electronics, household appliances, and industrial controls, where the requirements for speed, EMC, and thermal performance are lower.

In summary, advanced PCB and standard PCB differ significantly in their design principles, materials, manufacturing processes, performance, and application fields. Advanced PCB are ideal for high-end applications like high-speed data transmission and high-frequency communication, while standard PCB are better suited for everyday consumer electronics and appliances.