4 oz Copper PCB


  • Renders extremely good quality and friendly price
  • Producing standard model of 4 oz copper PCB
  • 10 years of experience in the design supplier field
  • Customized 4 oz copper PCB


What is the application of 4oz copper pcb?

◎First of all, the modern PCB industry uses 4 oz. copper thickness in electronic devices that require high technology. In addition, you can apply 4 oz PCBs in soldering equipment.

◎Power converters are configured using 4 oz PCBs. In addition, you can also find this PCB useful in space systems and high-tech radar systems.

◎In addition, the 4oz copper PCB can be used in automotive and solar panel systems. It can also serve for electrical or general power systems.

◎Control panels are available for different industries. 4oz PCBs play an important role in industrial panel manufacturing. You will also find 4oz PCBs in vending machines, automotive instrument panels, amplifier systems, and lighting systems.


Surface finish of Venture 4oz pcb

The surface finish is related to the coating of the material, which is usually located between the components of the circuit board. Applying this surface finish is necessary to ensure that the soldering of the circuit board components is tight enough.

Another reason why surface finish is important is that it protects the copper circuitry of the board. In addition, it protects the board from oxidation.

For 4 ounce PCBs, HASL – Hot Air Solder Leveling is the primary surface finish. This finish includes a double layer of metal coating and nickel. In addition, it is repairable and cost effective.

In addition to HASL, ENIG surface impregnation is also useful. ENIG stands for Electro-Nickel Impregnated Gold. This gold layer helps to protect the nickel layer.In addition, you can use lead-free HASL. All of these surface treatments help protect your 4 oz. PCB from any damage.

How survivable is 4 Oz CopperPCB?

The survivability of a 4 oz CopperPCB is very important. It must continue to work under adverse conditions.

Venture Electronics choose different types of materials because the manufacturing affects its survivability.We choose the dielectric material FR-4 or high-temperature polyimide.FR-4 works at 130 degrees Celsius, while high-temperature polyimide works at 250degrees Celsius.Extreme environmental conditions can affect the material of a 4-ounce copper PCB.

The printed circuit board industry has developed a number of methods,it allows you to check the integrity of a 4 oz. copper PCB.You can also use a test called TCT (Thermal Cycling Test).

You can use this test to test the resistance of a circuit by cycling the temperature from 25 degrees Celsius to 260 degrees Celsius.


Your Best 4 oz Copper PCB Partner

4oz copper PCB

4 oz Copper PCB

We are a professional 4 oz copper PCB design supplier in China for over 10 years of experience. We render our valued customers the very great products at the most affordable pricing. Venture can also supply other design that is related to 4 oz copper PCB like:

  • 4 oz Copper PCB 4 Layer
  • 4 oz 2 Layer Copper PCB
  • 4 oz Copper Base PCB
  • 12 Layers 4 oz Heavy Copper PCB
  • Led Driver 2 Layer 4 oz Thick Copper PCB
  • 4 oz copper PCB 2 Layers Power Supply

4oz copper PCB

Your Leading 4 oz Copper PCB Supplier in China

4oz copper PCB

The improved copper weight, along with a thicker plating and appropriate substrate in the through-holes can change a weak board into a long-lasting and dependable wiring platform. Heavy copper conductors can increase the entire PCB thickness considerably.  The copper thickness should always be considered during the circuit design stage.

Venture 4 oz Copper PCB design can render some benefits such as:

  • Capability to survive frequent exposure to excessive current
  • High tolerance capacity that makes it compatible with applications in rough situations
  • Compact product size due to several copper weights on the same layer of circuitry
  • Onboard high-power-density planar transformers

Venture expertise is a design supplier at a reasonable cost, heavy copper PCB that is of proven designs. Our engineering team can work with you to review your design to make sure that they can be supplied with the highest quality at the best overall cost. Venture ensures maximum control over quality and the ability to design and produce custom to customers’ specifications.

  • Heavy copper-plated vias pass the elevated current through the PCB and assist in transferring the heat to an outer heat sink
  • It also elevated temperatures and recurring thermal cycling
  • The amount of current a copper circuit can safely carry depends on how much heat rise

We are committed to excellence and our innovations in the 4 oz copper PCB are an example of our commitment. Venture is skilled in the greatest 4 oz copper PCB design supplier.  Our superior units come with full customer support. For value-added experiences, you can rely on us to give you a fair price. We are delighted to hear from you. 

Heavy copper PCBs are utilized for various purposes such as in planar transformers, heat dissipation, planar transformers, power converters, high power distribution and more. There is an increased request for heavy copper-clad boards in a computer, automotive, military, and industrial controls. Heavy copper printed circuit boards are also utilized in:

  • Power Distribution
  • Automotive Industry
  • Welding Equipment
  • Solar Panel 

If you are in need of a 4 oz copper PCB feel free to contact us for assistance.

4 Oz Copper PCB: The Ultimate FAQ Guide


This guide covers both the basic and advanced aspects of 4 Oz copper PCB.

So, if you want to be an expert in the copper PCB, read this guide.

What is a 4 Oz Copper PCB?

A 4 oz copper PCB is a thick/heavy copper PCB with a large current carrying capability.

The 4 oz copper thickness is derived from uniformly layering four ounces of copper over a square foot.

In multiple layers, the copper weight can be distributed.

You find the resulting thickness is 5.48 mils.

2 layer 4 oz copper pcb

 2 layer 4 oz copper PCB

What are the Benefits of using 4 Oz Copper PCB?

As a thick copper PCB, you find the 4 oz copper PCB with the following advantages.

  • Printed circuit boards with 4 oz copper are mechanically stronger at points of connection such as drilled holes.
  • You can transfer larger currents without affecting trace aspects such as width and spacing.
  • The surface area of the conductive path is increased.
  • Using 4 oz copper allows the effective extraction of dielectric material properties benefits.

How Close are Copper Traces on a 4 Oz Copper PCB?

The copper traces on a 4 oz copper PCB are placed at a minimum distance of 14 mils or 0.355 mm apart.

4 oz copper PCBs carry larger current values and therefore require wider trace spacing.

Spacing reduces the chances of tracking between traces.

Why are Materials with High Glass Transition Temperature used for 4 Oz Copper PCB?

The glass transition temperature is the temperature at which a material with glass property starts to change its state.

The glass transition is not desired for the substrate material as it negatively hampers the mechanical strength of the board.

The use of materials with high glass transition prevents the yielding of material in manifestations such as cracking.

Materials with low glass transitional are likely to succumb to high-temperature operations such as soldering.

Furthermore, materials with high glass transition show durability when subjected to increased temperature values.

Moreover, they possess a low thermal expansion coefficient and the ability to withstand long delamination processes.

Are 4 Oz copper PCBs available in Double-sided Boards?

Yes, they are.

You can find 4 oz copper PCBs in a double-sided formation.

Double-sided boards are printed circuit boards where both sides of the board are populated.

Such a board configuration allows for increased board density and reduces board size area.

Double sided PCB

 Double sided PCB

What is a Schematic Diagram for a 4 Oz Copper PCB?

A schematic diagram for a 4 oz copper PCB is a representation that captures various elements of the board.

Schematics are useful in visualizing the 4 oz copper board design, allowing for adjustments and corrections beforehand.

Some of the information included in the schematic diagrams includes:

  • The points on the board for placing the components
  • The ratings of components
  • Procedures to be used in aligning the board and tuning process
  • The values to be used for tolerances and cases
  • The lines with impedance control
  • Arrangement of layer
  • thermal concerns for the construction

What Systems Use 4 Oz Copper PCBs?

You find 4 oz copper PCBs used in circuit systems requiring large current capabilities.

This kind of circuitry finds common use in industrial applications and military use.

Distribution panels for power and control systems for weapons are such uses.

What are some of the Design Considerations for Assembly for a 4 Oz Copper PCB?

Designing PCB for assembly is a design strategy that seeks to describe how the board populates will be affixed to the bare board.

The following factors are important when designing for PCB assembly.

  • It is important to establish how much the components will be spaced during assembly. The number of components required is useful in determining the spacing requirements.
  • The components sizes are another factor to be considered while designing for assembly. Large components will require large board space and therefore affect overall spacing strategies.
  • When using both leaded and non-leaded components, the design should ensure their separation on the board.
  • Exposed vias should be sealed and filled to avoid inflow of solder during when components are being attached to the board.
  • When CAM systems are to be used the set up should be simplified to allow easy placement of components.

What are some of the Major Processes involved in Making a 4 Oz Copper PCB?

There are several processes involved in the making of a 4 oz copper PCB.

You find that while the fine aspects of the manufacturing process may differ by different products, they follow a similar overall strategy.

To make a 4 oz PCB, copper layers of the required weight are gathered alongside other material such as prepreg.

The number of copper layers may vary according to the layer count.

However, the total used should correspond to 4 oz copper.

When more than four layers are required, vias have to be drilled.

Vias are used to connect the inner layers and the inner layers to the outer layers.

These are the buried and blind vias respectively.

The layers are bound together in a lamination process and prepped for the etching process.

The etching process is where the conductive copper trace is made.

Preceding the etching process is a procedure to develop a photoresist which is used to expose the unwanted parts for etching.

You find that every layer will undergo the drilling process through to the etching process.

Thereafter, the photoresist that overlays the conductive pattern is removed exposing the bare copper path.

On removing the resist, a solder mask is used to cover the copper trace pattern.

The solder mask has two major functions. It protects the copper from oxidizing while ensuring the soldering process does not encroach to unwanted areas.

A finish is applied to the surface that exposes the conductive copper path.

It also ensures the surface is ready for component placement.

A silkscreen is then added for informational purposes.

Computer-controlled systems are used to attach components on the board for large productions.

Manual assembly can also be done.

The 4 oz copper board with attached components is then packaged ready for delivery.

Why is Thermal Management needed in 4 Oz Copper PCB?

Thermal management refers to the handling of temperature-related changes on the 4 oz copper board.

Temperature changes can arise due to the excess dissipation of power in the form of heat energy.

Additionally, extreme external temperatures in the environment can result in a board temperature rise.

Thermal management is important in ensuring the board does not succumb to components failure.

Electrical components in the wake of increased temperatures can overheat and capitulate.

Thermal management provides an efficient way to maintain a good working temperature.

What are the Properties of the Substrate Material used in 4 Oz Copper PCB?

12 layers 4 OZ PCB

 12 layers 4 Oz PCB

The fire retardant material is used to make the substrate for the 4 oz copper PCB.

In particular, the FR – 4 is the most common fire retardant variant utilized in the lamination process.

You find the FR – 4 has a strong and rigid material structure with good insulation properties.

The following properties make the use of FR – 4 popular:

  • It has a high temperature for decomposition
  • FR – 4 has a high temperature for glass transition
  • It can be used for both assembly processes: with lead and also lead-free
  • It has good thermal stability with a low thermal coefficient of expansion
  • The FR – 4 had good dielectric properties

How are Components attached to the 4 Oz Copper PCB?

You find many printed components are surface-mounted on printed copper boards.

The 4 oz copper board is no different.

Here, you can find components that are surface-mounted while others are connected through-hole.

For multilayer formations, through-hole mounted components are placed at the top.

Surface-mounted components, on the other hand, are found at the bottom.

Surface-mounted components are smaller and less bulky allowing them to easily fit in lower layers.

What are the Rules Guiding Component Placement in 4 Oz Copper PCB?

Electronic components are the major populates of a 4 oz copper PCB.

PCB Electronic components

 PCB Electronic components

You find the board surface with components such as electronic connectors, capacitors, resistors, diodes, and transistors.

To place electrical connectors on the board the following guidelines are useful:

  • The landing pads for components need to be placed at fixed and effective locations.
  • Components are to be positioned such that there are no longer bare traces.
  • The positioning of components should be parallel to the edges of the board
  • Related components should be placed close together.
  • Integrated circuit chips need to have a uniform configuration. They should be positioned either facing upwards or downwards otherwise oriented to the left or the right.
  • The IC chips should have their primary pins identified and similarly oriented
  • Positive terminals to polarized electrical components should be marked and faced in the same direction.
  • The component landing pads and copper traces have to uniformly spaced.

How is the Lamination Process Carried Out for Multilayer 4 Oz Copper PCB?

5 Multi layer PCB

 Multi layer PCB

Lamination is a process used to hold together layers in a multilayer formation.

The layers are assembled in the design order where the substrate is placed between successive copper layers.

The positioning of the layers should ensure no interference of the succeeding processes such as drilling.

Lamination is a process carried out under high temperature and pressure.

The high temperature is why the substrate material needs to have a high glass transition temperature.

The layers are subjected to the temperature-pressure conditioning for no fewer than 30 minutes.

After the lamination process is complete, the laminate is allowed to cool.

This allows the resin to set allowing the formation of a rigid structure.

An inspection is carried out to determine whether the resulting product is as per the design specifications.

Can the 4 Oz Copper PCB Support Both Axial and Radial Lead Components?

You find that components with either axial leads or radial leads can be fitted to a 4 oz copper PCB.

Axial leads protrude from the sides of a component parallel to the surface.

Radial components have leads extending from a single side of the component.

Axial leaded components adhere to the board surface when fixed.

Radial leaded components seem to extend from the board surface.

While components with axial leads consume a lot of board space, components with radial leads are less occupying.

Why are Surface-mounted Components popular on 4 Oz Copper PCB?

Surface-mounted components are leadless components that are attached to the board by soldering their bases to the board surface.

The popularity of surface-mounted components on the 4 oz copper PCB is due to the following reasons:

  • Surface-mounted components are attached to the board without the need for drilled holes.

Eliminating the need for holes greatly reduces the cost of making a 4 oz copper PCB.

  • Surface-mounted components are small and their use increases the board density.
  • The process of mounting these components to the board is less time consuming than through-hole components.
  • Surface-mounted components can be placed on both sides of the copper board. Through-hole components can only be placed on the top surface.

What Component Package Types can be Accommodated on the 4 Oz Copper PCB?

You will find several package types for components accommodated on the 4 oz copper PCB.

The package types available allow for both through-hole mounted and surface-mounted components to be attached to the board.

Some of the common packages include:

The ball grid array package is stylized by a grid-like formation of small balls at the bottom of the component.

The 4 oz copper board has a landing pad with round depressions to support components with such packages.

The single-in-line package has leads for attachment extending from one side.

The 4 oz copper PCB has sockets defined with cylindrical depressions to allow for the insertion of chips with such packages.

Dual-in-line package is similar to the single-in-line package but with two sides having leads attached to them.

They connect to points on the board surface with sockets for both sides with leads.

Connection ports are also provided for both small-outline packages and thin small-outline packages.

Both these package types are small consuming reduced space on the board surface.

The thin small outline package has fine-pitched leads with a low profile.

What are some of the Specifications to Consider when making a 4 Oz Copper PCB?

First, a 4 oz copper board needs the copper material weight of a thickness attributable to four ounces of copper.

4 oz copper boards are used in applications with large current demands.

However, several applications can have different needs despite their common current intensity.

To make a 4 oz copper board-specific your needs, the following specifications are useful:

  • The width of the copper traces and spacing requirements
  • The number of layers desired for your board
  • The material composition for the board structure
  • The final thickness of the board
  • Impedance control
  • The location of vias and whether they should be filled or plated
  • The type of surface finish
  • Choice of solder mask

Can 4 Oz Copper PCBs be used for High-frequency Applications?

Yes, they can.

You find 4 oz copper boards can be used for applications with high-frequency demands.

To support increased rates of signal flow, 4 oz copper PCBs have to be made with wider trace widths.

To allow for wider trace widths 4 oz copper PCB can be made in multilayer formation.

Using multiple layers allows for the board to adhere to the recommended minimum trace spacing.

Additionally, close tolerances are kept to reduce impedance levels.

You also find the dielectric properties of the materials used important in high-frequency handling.

The FR- 4 material has good dielectric properties with high material compatibility.

Heavy copper PCB

 Heavy copper PCB

How is Signal Interference Handled on the 4 Oz Copper PCB?

Signal interference is an onboard occurrence that results from the presence of different signals on the board.

The signals originate from the varied component population.

To alleviate interference levels, the following strategies are commonly used on the 4 oz copper PCB:

  • Components with high signal values are located as further apart on the board
  • The copper traces are configured at right angles when interposing between layers
  • The occurrence of extended parallel copper traces are reduced be design alterations
  • Use of guard rings around components

What are Some of the Standards used for the 4 Oz Copper PCB?

Some of the popular standards of thick copper PCB include:

· BS-6221-3

A guide for the design and use of the 4 oz copper PCB is provided for in this standard.

· BS-EN-61188-5-3

This standard establishes guides for the 4 0z copper PCB assembly process.

· BS-QC-200012

A schedule for monitoring procedures used in by facilities n fabricating 4 oz copper PCB is provided in this standard.

· DD-IEC/PAS-61249-6-3

This standard attaches specifics concerned with the finished fabric used in lamination and woven from “E” glass.

How is 4 Oz Copper PCB Tested?

The Automated Optical Inspection test can be used for the 4 oz copper PCB.

A camera is used to identify defects and missing parts or sections on the board.

You find this method involves no direct contact of the board preventing contamination.

The automated optical inspection is carried out progressively as the board is fabricated.

It can be used after completing every fabrication process.

This approach ensures defects are not carried over across multiple processes making them difficult to deal with.

A bare board, when inspected, can identify faults such as violations in trace widths and spacing, shorts and missing pads.

An inspection of a loaded board can identify component defects such as misplacement, wrong polarity location or absence.

As you can see, there are many things you should consider when evaluating 4 Oz.

The best part, this guide has highlighted everything you must consider.

For questions or custom orders, contact us now.

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