Once the customer order and PCB design file is received the PCB Global production engineering team will process the manufacturing data which is required at every stage of PCB fabrication. This ensures that your Printed Circuit Boards are manufactured to your specifications. There are multiple combinations when it comes to PCB finishes and specifications. Listed below is an example of a typical 4-layer multi-layer data required on a job card to ensure that all customer manufacturing conformance is adhered to:

PART NUMBER– PCB GLOBAL 123456-A

LAYER – 4 layer

QUANTITY– 512pcs

PRODUCTION PANEL SIZE– 450 x 650 mm

PRODUCTION PANEL QUANTITY- 32

UNIT SIZE– 90 x 150 mm

PANEL SIZE– 300 x 200 mm

BOARDS PER PANEL– 4

MATERIAL– FR4 High TG=170 - S1170

PCB THICKNESS– 1.6mm

COPPER FOIL– 18um Copper

PRE-PREG– 7628HR RC: 47% 0.21mm

CORE – 1.0mm 35/35um Copper

SOLDER MASK COLOUR– Blue

COMPONENT LEGEND COLOUR–  Yellow

SURFACE FINISH– Immersion Gold – ENIG 2-3u”

PROFILING– Panel route with break tabs

This break-down ensures that the operators at each stage of fabrication will assume the precise finishes required on this part number as it flows through the production line. A typical workflow for a standard 4-layer through the PCB Global processes is demonstrated through many small processs.

Firstly the inner layer material is cut and the inner layer laminating and exposure is completed. Developing, etching and AOI inspection is the followed up by copper foil and pre-preg cut and multilayer lamination and pressing. Next the CNC drilling will take place in preparation for Desmear and Electrolysis Copper plating. Once this is complete, laminating and exposure is pattern plaited (Copper & Tin/Lead) and etched with a further AOI Inspection. LPI solder mask along with the component legend silkscreen is applied and then sent to bare board testing. Immersion gold is added with a further CNC routing. The boards are then clarified with deionised water before the final QA. The boards are then packed and dispatched to your requested delivery address.

PCB Global manufacture 1 layer, 2 layer and the high tech 4 layer Aluminium PCB’s for the worldwide electronics manufacturing industry. Applications for Aluminium PCB’s are found predominantly in the lighting, motor drives, relays, automotive, power conversion and 3D printer industries. Using Aluminium PCB Technologies assists in lower equipment operating temperatures which improves the LED’s with consistent colour and brightness, in turn, increasing the LED component life.

For solid state relays Aluminium PCB’s offer great thermal efficiency and are mechanically robust for all heavy industry applications. The correct dielectric choice will also provide the electrical isolation required to maintain operating parameters and meet safety regulations as well. Currently 80% of all Aluminium PCB’s are manufactured as 1 layer with the lighting industry being the largest consumers.

The stack as illustrated below consists of:

Base Metal Layer:Aluminium – generally 1.0 to 2.0mm thickness, 1.5mm being the standard.

Dielectric Layer:Not only to bond the copper circuit layer to the aluminium but more importantly offer the required electrical isolation with minimal thermal resistance.

Copper Foil:As per any standard printed circuit board, the copper foil will be processed and etched to the required circuit layer design.

PCB Global offer the above technologies for Aluminium Printed Circuit Boards on our easy to use online portal -  http://www.pcbglobal.com/quote/aluminium-pcbs/

Printed Circuits Boards are cleverly designed items that are used to not only connect electronic components but also mechanically support the functions of many electronic devices. The market for bare PCB’s worldwide was valued at $60.2 Billion in 2014 (US). Components are connected and operated by the conductive pathways, tracks or what is known as signal traces which are etched from copper sheets. This connection is made possible by the distinction between the copper sheets and the non-conductive substrate laminated on to the board. The resistance of the board is determined by the width and the thickness of the traces that expose the copper. The use of the board is also considered when inserting the tracks and traces for example some power and ground traces are usually wider then signal traces. The size and capability of these tracks and traces are described as impedance control. PCB Global not only delivers Printed Circuit Boards to your specifications, we can also assist with your impedance control requirements with predetermined layer stack up including track width and spacing recommendations to ensure impedance matching.

FR4 (Flame Resistant 4) is the most commonly used epoxy which is a woven fiberglass cloth impregnated with the epoxy resin. It has good insulation properties with good arc resistance making it very useful to both single and multilayer boards. The copper is laminated onto the FR4, providing a greater distinction of the conductive pathways as previously described that the FR4 has a high insulation effect. Multilayer PCB’s will have multiple layers of materials which will be laminated together. In some cases, multilayer boards may be required to contain a solid copper layer to act as a shield or ‘ground plane’ for power return.

Copper thickness in any single or multilayer PCB will determine the current-carrying capacity of the board. It is preferable to use heavier copper to increase the carrying capacity as well as increase the resistance of thermal strains. 1oz and 2oz copper are the preferred and more common choices for many single and multilayer PCB’s. Chemical etching is a process using lead and tin to electroplate the copper to increase the thickness. This is achieved by a mixture involving either ammonium persulfate or ferric chloride. The purpose of the chemical etching is to etch away the excess copper on the areas that should not contain copper. The solder, tin, gold or nickel used to plate the PCB acts as a corrosion resistant coating/barrier. The most common method is hot air solder levelling or HASL.

Components such as resistors, capacitors and active devices are usually soldered onto the bare PCB. In some cases, more advanced PCB’s will have their components embedded in the substrate. This offers greater connection and conduction, advancing the function of the loaded PCB. Components embedded throughout different layers of the PCB are made possible by the connection of vias. Multilayer PCB’s in this case will always allow for a higher conduction through component density. In the case that the board does not have any embedded components as described above, the more correct terminology for this item is know as a Printed Wiring Board (PWB) or Etched Wiring Board. It is common for the PWB to be known as a Printed Circuit Board or PCB.

Through-hole technology is the method commonly used to mount electronic components by leads on the boards. The components are soldered onto the copper traces usually on both sides of the board. The soldering can either be done manually or by a wave soldering machine which increases the efficiency. Surface mount technology (SMT) is another method by which the components were redesigned to enable more efficient soldering on the PCB rather then passing wires through the board. This also allows for smaller PCB assemblies and enables a higher density of circuits. PCB Assembly is also known as ‘PCBA’. Assembled PCB’s can be very sensitive to static therefore is placed in anti-static bags during transport to their destinations. When handled, the person must be earthed as the accumulation of static can damage or destroy the components.

Contact the team at PCB Global or proceed to the online quote page for your free and instant quotation today!

PCB Global offer 1 layer, 2 layer and 4 layer Aluminium Printed Circuit Boards online with 1W/m-K and 2W/m-K dielectric as standard options

At PCB Global, we offer a range of Solder Mask colour options such as green, blue, purple, red, yellow, white, black matt and black gloss as well as the option to have no solder mask. These options apply to our FR4 (2-20 layer), Full Spectrum (1-40 layer) and Aluminum Printed Circuit Boards.

Once you have decided on your design of your Printed Circuit Board you need decide on options that will suit your requirements for your board. One of the options is the choice to have a solder mask and/or silkscreen legend. Why not deviate from the standard green printed circuit board and pick a color that will match your corporate logo?

It is important, even for your prototype PCB’s to have a solder mask and silkscreen legend for many reasons. Without the solder mask, your board would be plain copper, or what is known as a bare board with Tin Plating (tin, lead and usually a silver mixture). The Tin plating is placed on the bare board to allow soldering to take place and also slows down the rate of oxidation in the copper.

Today the Solder Mask application is LPI (Liquid Photo Image), which is applied to the production panel in a silkscreen printing process one side at a time. It is then dried in an oven and then the solder mask film is aligned to the pads and bared in an UV exposing machine then placed in a conveyorised developer to remove all the areas (SMT pads and holes) that will be required to have the surface finish applied later like HASL, Immersion Gold, OSP, etc.

The solder mask is a coating that protects the circuit from electrical shorts and corrosion as well as providing electrical insulation, allowing higher voltage traces to be placed at a closer proximity to each other. The most important function of the solder mask is to keep the solder on the pads, which will reduce the formation of bridges or unintended connections. In some cases, such as wave soldering, solder masks are a critical element of this process whereas in other cases, it enables a more efficient and more accurate hand solder job as the solder covers the entire board except for the pads. The colour of the solder mask is not vital to the function of the board, rather providing a distinctive colour to your design and enabling better visibility to your copper connections. There is an option to have a partial solder mask that will cover a specified part of the pad, rather then exposing the entire pad.  This would be ideal if there is a pad underneath a chip, leaving the pad exposed and vulnerable to solder bridges.

Exposed vias are usually covered with the solder mask and silkscreen as this will provide protection from corrosion and electrical shorts while also providing a larger surface area. If a board does not contain a solder mask, it is not an issue, it will mean that care must be taken when soldering as the solder mask reduces cost of mistakes and time taken to complete the solder and components.

Physical and Electrical Properties of the LPI Solder Mask Include:

Next comes the option for the Silkscreen layer which is also called a ‘legend’ as this is a non-conductive ink used to place traces on a board as a means of instructions. It is utilised as a pathway to allow multiple traces and pathways, as this will not be conductive in the copper layers alone as the copper traces would interrupt the circuit. This also makes better use of the space on the board and provides a better contrast for a faster assembly. For prototype PCB’s the silkscreen is usually restricted to the top part of the board but in some cases it can be placed on both sides of the board if required.

PCB Global was created to minimize time taken in waiting for quotes and orders to be processed. We utilise these processes by adding you, the designer and engineer, to quote and order PCB’s to your specifications 24/7, 365 days a year, allowing you to test or create your product for your needs at a faster rate.