PCB / PCBA Technical terms
|Assembly Bill of Materials(BOM)
Bill of Materials is a list of all the parts that are needed for the PCB Assembly and matches those parts to the
Reference Designators in the PCB layout.
|More details about Bill of Materials
Aspect Ratio is calculated by dividing the maximum board thickness with the smallest drilled hole diameter size
specified for that board design.
|More details about Aspect Ratio
|The annular ring is the width of the copper area around a via to connect it with the PCB trace network.
|What is Annular Ring in PCB?
|Bare board testing
|Electrical Testing of the non-populated PCB.
|Introduction and Video can be fould at here
|Blind and buried via holes
|A Blind Via connects an Outer Layer to one or more Inner Layers but does not go through the entire board. A Buried Via connects two or more Inner Layers but does not go through to an Outer Layer.
|Introduction about blind and buried via holes
BGA is abbreviated from Ball Grid Array, a form of surface mount technology (SMT). BGA is now chosen more
commonly in circuit design.
|What is BGA?
|As part of your design’s Gerber files, we require an outline of your board’s final shape.
|What is Board outline?
|The thickness given in mm based on the base materials used including copper foil.
|What is the board thickness?
|Bottom side of the PCB.
|Introduction for bottom side of the PCB
|Defined build of a PCB such as number of layers an their sequence.
|What is the Buildup of a PCB?
|Carbon Ink normally used for keyboard contacts, LCD contacts and jumpers.
|Introduction for carbon contacts
|Conductor clearance is the distance between traces or other copper elements.
|What is Conductor clearance?
|Che Ni/Au or ENIG
(Electroless Nickel Immersion Gold)
|ENIG, Electro less Nickel Immersion Gold, also called Che Ni/Au, chemical nickel gold or also known as soft gold.
|1. What is ENIG?
2.Surface finishing comparision
|Copper Foils is the base copper thickness applied on OUTER and INNER layers.
|What is copper foil?
|Copper clad FR-4 laminate materials are measured using ounce(oz.)weight per square foot.
|Copper weight & Heavy copper for materials
|A rigid base material laminate with copper on one or two sides.
|The core of a PCB
|Cu is the chemical abbreviation for Copper
|What is Cu(Copper) mean?
|Centroid File/Pick and place file
|We recommend you include design drawings for projects with a high number of layers or components.
|PCB Manufacturing drawing and PCB assembly drawing
|Removing a specific area of the Outer Layer of the PCB to a specific depth.
|Introduction for depth control routing.
|Double gold(Full-Body + Selective Gold)
|Introduction for Double gold
|Drill / Route File
Drill Files define the size and coordinates of any holes to be drilled in a PCB design.
|Introduction about Drill / Route File
PCB etching is the process of selectively removing unwanted copper from a PCB’s copper-clad substrates.
|What is Etch factor?
Edge beveling is the process of making a transitional edge between two faces of a PCB usually performed on the outer edge of the PCB
|What is Edge Beveling?
|Edge Connector Plating
|A layer of gold plated to the fingers of the Edge Connector.
|What is edge connector plating?
Electroless Nickel / Electroless Palladium /Immersion Gold (ENEPIG) is an advanced and complicated surface finish.
|Electrical Testing Requirements
Electrical testing is used to ensure that no error occurred during the production process that might have introduced unwanted short or open circuits into the PCB’s copper layers.
|An Optical target.
|Finished hole size
|The finished hole size or ENDHOLE is the diameter that the PCB designer specifies in his PCB layout.
|PCB finished hole size
|Finish board thickness
Finished overall board thickness can be measured from a PCB’s top layer to its bottom layer, including the solder mask and copper layers.
Full Body Hard Gold
Full Body Hard Gold also known as Hard Electrolytic Gold,is a layer of gold with hardeners for increased durability,plated over a barrier coat of nickel using an electrolytic process.
|Hot Air Leveling Lead Free Tin (Sn)
Heatsink paste is a paste that consists of a special polymer which is filled with finely dispersed solid particles.
|What is Heatsink paste?
|The number of holes per dm² of the board surface.
|What is hole density?
Immersion Tin is a method using a chemical process to apply a very thin tin layer over the copper layer.
|What is Immersion Tin?
|What is Immersion Silver?
Impedance Controlled PCBs are fabricated with tightly controlled dimensional tolerances to ensure the PCBs have signal transmission lines with accurate impedances. Click the link to know more about Impedance controlled PCB types / Impedance calculators / Impedance models / Impedance Affect stack-up /TDR calculations.
|Impedance controlled PCB
|Laminate Materials selection
|PCB Laminate Materials selection
|Lead free finish
|Final finish applied to the soldering areas of the PCB to prevent oxidation and to them easier to solder.
|A type of short, sometimes referred to as a high-resistance short.
|Text printed on top of the Soldermask.
|Micro section of a PTH
|A cross section of a PTH Hole.
|Introduction for Micro Section of a PTH
|Used to form the contour of the PCB’s or Panels.
|Milling and routing
Micro-vias can connect adjacent layers, allowing a single multilayer PCB to hold more circuit traces, which increases PCB circuit density.
|What is micro via?
Overall Finished Profile Tolerance
A surfaces profile is a 3-dimensional tolerance zone outline around a surface plane defined by using basic radii dimensions, coordinate dimensions, angular dimensions.
|What's the Overall Finished Profile Tolerance?
Solder Mask opening: The place where there is no solder mask is called the solder mask opening.
Organic Surface Protectant (OSP) is a type of water based, organic surface finish that is typically applied to copper pads on a PCB.
|Introduction about OSP/ENTEK
|The Outer Layer(s) of the PCB either the TOP or BOTTOM side.
|What is the outer layer in PCB?
Such an array is also an advantage for board assembly; larger pick and place machines, having to be loaded less often, reduces handling costs.
|What is the panel border,PCB board array,panelize?
|Panel X-out,Cross out
It stands for the defective boards in PCB panels, and X marks are usually marked on the top.
The Profile, also known as contour or outline, represents the outer edges of a printed circuit board as well as its inner recesses like drill holes.
|What is PCB Profile?
|The PCB Spacing defines the extra space you want between different PCB’s on the Customer Panel.
Panelization is a way to safely manufacture multiple PCBs simultaneously while keeping the PCB’s separation process afterwards as smooth as possible.
|Introduction for PCB Panelization
|PCB Separation Ways
|Pre-cut the boards in a Customer Panel for easy removal after assembly.
|What are the PCB separation ways?
|Also know as Peel-off Mask is a protective coating that can be easily removed.
|PHD or Tool size
|The diameter of the Tool used in production to drill the hole.
|Plated holes on the board edge
|Plated through holes in the edge of the board.
|What is Plated Holes on the Board Edge?
|PCB assembly process
|1.To manufacture the actual bare PCB;
2.To populate it with components.
|The PCB Assembly Process-Overview
|Pick and place machine set up
|The Pick & Place Setup is the information and programming of the machines that will place the components on the PCB with the correct position and orientation
|Introduction for Pick and place machine set up
|Prepreg is a bonding material used in the fabrication of multi-layer PCB boards,which,after curing,has the same properties as the core / base layer materials.
|What’s the Prepreg Designation and Thickness?
|Pressfit holes are plated holes with tighter tolerance, which are used for through-hole components that are not soldered to the board
|Introduction for Pressfit holes
|PCB Laminate Materials
|Laminates are the primary material used in PCB fabrication, and different laminates have different properties,performances, and associated costs.
|PCB Laminate Materials selection
|Round edge plating
The edge of the board is plated with copper and then the final finish such as HAL.
|What is Round-Edge Plating on PCB?
|An electrical connection between two or more nets or isolated points that should not be connected.
|What is a short in circuit?
Stacked micro-via is a type of compound design structure which stacks micro-via on top of each other.
|What is stacked micro-via?
|SMD or Surface mount device
|Surface mounted Device.
|What are SMD components?
|A solder mask is a robust, permanent coating that is laminated over the copper traces of a PCB. This layer is sometimes called the “solder stop mask” or “solder resist”.
|Options and Requirements for Solder Mask
Surface finish choices
Hopetimepcb offers a variety of different surface finish choices
|Introduction for Surface finish choices
|What Data should be prepared for solder paste cover to the PCB board?
|Solder paste data prapation
|Stainless Steel template for applying Solder paste onto the board.
|Introduction for stencil
|Tg stands for Glass Transition Temperature and is one of the parameters of a base materials.
|What is PCB material Tg mean?
|A hole of many names-clearance hole,thru-hole,via,plated thru-hole,ect--
|What is through hole on PCB?
|Top side of the PCB.
|What is the Top side of a PCB?
|Tear Drop Pads
Tear Drop Pads are an extra feature that adds additional copper at the junction of annular rings with PCB traces.
|What is Tear Drop pads on PCB?
|Hopetimepcb will perform a variety of tests over the course of PCB fabrication and assembly with the reports for these tests
|Turnkey PCB assembly
Turnkey PCB assembly manufacturers are experts in the complex set of processes required to produce low-cost and high quality PCBs with fast turn times.
|The advantage for turnkey PCB assembly manufacturing?
|Testing for PCBA
PCBA test is an important part of controlling the quality of products in the PCBA process
|What types of standard testing are in PCBA?
|Scores are essentially V-Shaped grooves made on a panel with multiple boards so the PCBs can be easily separated.
|What is V-Score in PCB manufacturing?
|A hole that creates an electrically connected through the PCB.
|What is a via holes in PCB?
|The filling of Via Holes with Resin
|What is Via filling in PCB manufacturing?
|Warp and Twist
|The distortion of the PCB.
|What are Warp & Twist in PCB?