Printed Circuit Boards

Single Sided PCBs contain only one layer of conductive material and are best suited for low density designs. Single sided PCB’S have been around since the late 1950s and still dominate the world market in sheer piece volume.  Single-sided printed circuit boards are easily designed and quickly manufactured. They serve as the most cost effective platform in the industry.

How Are Single Sided PCBs Made?

One thin layer of thermally conductive but electrically insulating dielectric is laminated with copper. Soldermask is usually applied on top of the copper.

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Benefits of Single Sided PCBs

  • Ideal for simple low-density designs
  • Lower cost, especially for high volume orders
  • Lower probability of manufacturing issues
  • Popular, common, and easily understood by most PCB manufacturers

ECMC produces prototype, midrange and high volume Single Sided circuit boards, with a copper thickness from 1 to 20 ounces.  Operating temperatures range from 130 C to 230 C.  Single sided boards are available with surface finishes including Organic Surface Protectant (OSP), Immersion Silver, Tin, and Gold plating along with both leaded or lead-free Hot Air Solder Level (HASL).

Although Single Sided PCBs are relatively simple, they can still be used in very complex devices:

  • Power supplies
  • Relays (automotive and industrial)
  • Timing circuits
  • Sensor products
  • LED lighting
  • Radio and stereo equipment
  • Packaging equipment
  • Surveillance
  • Calculators
  • Printers
  • Coffee makers
  • Vending machines
  • Solid state drives
  • Camera systems

Double Sided PCBs (also known as Double-Sided Plated Thru or DSPT) circuits are the gateway to higher technology applications. They allow for closer (and perhaps more) routing traces by alternating between a top and bottom layer using vias. Today, double sided printed circuit board technology is perhaps the most popular type of PCB in the industry.

How Are Double Sided PCBs Made?

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Benefits of Double Sided PCBs:

  • More flexibility for designers
  • Increased circuit density
  • Relatively lower costs
  • Intermediate level of circuit complexity
  • Reduced board size (which can reduce costs)

Applications of Double Sided PCBs

There are near limitless applications for old and new designs. Fine line surface mount, ultra high copper build, high and low temperature, Solder coated, Silver, and Gold finishes are just a few examples of DSPT applications.

The following are applications in which Double Sided PCBs can be used:

  • Industrial controls
  • Power supplies
  • Converters
  • Control relays
  • Instrumentation
  • Regulators
  • UPS systems
  • Power conversion
  • HVAC
  • LED lighting
  • Hard drives
  • Printers
  • Phone systems
  • Power monitoring
  • Automotive dashboards
  • Line reactors
  • Test equipment
  • Amplifiers
  • Traffic systems
  • Vending machines

Multilayer PCB is a circuit board that has more than two layers.

Unlike a Double-Sided PCB which only has two conductive layers of material, all multilayer PCBs must have at least three layers of conductive material which are buried in the center of the material.

How Are Multilayer PCBs Made?

Alternating layers of prepeg and core materials are laminated together under high temperature and pressure to produce Multilayer PCBs. This process ensures that air isn’t trapped between layers, conductors are completely encapsulated by resin, and the adhesive that holds the layers together are properly melted and cured. The range of material combinations is extensive from basic epoxy glass to exotic ceramic or Teflon materials.

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The figure above  illustrates the stackup of a 4-Layer/ multilayer PCB.  Prepeg and core are essentially the same material, but prepeg is not fully cured, making it more malleable than the core.The alternating layers are then placed into a lamination press. Extremely high temperatures and pressures are applied to the stackup, causing the prepeg to “melt” and join the layers together. After cooling off, the end result is a very hard and solid multilayer board.

Benefits of Multilayer PCBs (compared to single or double-sided PCBs)

  • Higher assembly density
  • Smaller size (considerable savings on space)
  • Increased flexibility
  • Easier incorporation controlled impedance features.
  • EMI shielding through careful placement of power and ground layers.
  • Reduces the need for interconnection wiring harnesses (reduces overall weight)

Applications of Multilayer PCBs

While the weight and space benefits of multilayer PCBs are especially valuable forAerospace PCBs, multilayer PCBs are also beneficial to applications where “cross-talk” levels are critical. These are a few other the applications using multilayer printed circuit boards:

  • Computers
  • File servers
  • Data storage
  • Signal transmission
  • Cell phone transmission
  • Cell phone repeaters
  • GPS technology
  • Industrial controls
  • Satellite systems
  • Hand held devices
  • Test equipment
  • X-ray equipment
  • Heart monitors
  • Cat scan technology
  • Atomic accelerators
  • Central fire alarm systems
  • Fiber optic receptors
  • Nuclear detection systems
  • Space probe equipment
  • Weather analysis

Heavy Copper PCBs are printed circuit boards with 3 or more ounces of finished copper in the inner and/or outer layers.

How Are Heavy Copper PCBs Made?

ECMC utilizes a unique process referred to as “Laminated Deposition”. This combination of processes allows extreme copper thickness requirements to become very practical and cost effective. The process utilizes heavy base copper that delivers consistent and reliable high power circuits when placed in our plating and etching systems, allowing us to produce well-defined track edges, finer lines, and finer spaces.

Benefits of Heavy Copper PCBs

  • Elimination of complex wired buss configurations
  • Increased current carrying capacity
  • Increased endurance to thermal strains
  • Optimized use of exotic high temperature materials with lower probability of circuit failure
  • Ability to incorporate multiple copper weights on the same layer of circuitry (layer count reduction)
  • Added copper plating in the heat vias (thermal resistance reduction)
  • Selective areas plated with heavy copper can function as a heat sink or interface to cold plate (built-in heat sinks)
  •  Integration of high-current circuits and control circuits on a single PCB

Applications of Heavy Copper PCBs

Demand for heavy copper-clad circuits in automotive, computer, industrial controls, and military is growing very fast. More than 80% of the existing PCB manufacturers are limited or not capable of producing reliable heavy copper printed circuit boards.

  • Solar power converters
  • Safety and signal systems
  • Renewable energies and storage pumping plants
  • Torque controls
  • High power rectifiers
  • Overload relays
  • Power converters for railway systems
  • Power line monitors
  • Traction converters for rail applications
  • UPS systems
  • Electric vehicle charging (commercial and industrial)
  • Protection relays
  • Excitation systems for power regulators
  • Position control systems
  • Power grid switching systems
  • HVAC systems
  • Energy storage and power grid back up
  • Nuclear power applications
  • Line reactors
  • Hydro-electric plants
  • Surge protectors
  • Fuse blocks
  • Welding Equipment
  • Weapons control systems
  • Radar systems

The driver behind the demand of copper PCBs is ever increasing power, performance, and cost requirements.

Aluminum Printed Circuit Boards Contain a Thin Layer of Thermally Conductive Dielectric Material that Transfers Heat

There are many names for these products; Aluminum clad, aluminum base, Metal clad printed Circuit Board (MCPCB), Insulated Metal Substrate(IMS or IMPCB), Thermally conductive PCBs, etc… but they all mean the same thing and perform the same way.

How Are Aluminum PCBs Made?

A thin layer of thermally conductive but electrically insulating dielectric is laminated between a metal base and a copper foil. The copper foil is etched into the desired circuit pattern and the metal base draws heat away from this circuit through the thin dielectric.

Benefits of Aluminum PCBs

  • Heat dissipation is dramatically superior to standard FR-4 constructions.
  • The dielectrics used are typically 5 to 10 times as thermally conductive as conventional epoxy-glass and a tenth of the thickness
  • Thermal transfer exponentially more efficient than a conventional rigid PCB.
  • Lower copper weights than suggested by the IPC heat-rise charts can be used.