Active Component: A device that requires power/voltage to operate. Usually the device has a pin that is labeled Vcc. An intigrated circuit is an active component. A resistor is not.
Analog: A term used to descibe a variable voltage source. For example, an analog signal that operates between 0 and 5 volts can have an infinite number of positions. A digital signal can have only two (either a zero "0", or a one "1") which ideally mean it's either at 0 volts or at 5 volts. Analog is considered the opposite of digital.
Anode: The positive "+" side of a device. This is opposite of negative or cathod "-".
Aperture: This term usually referred to an opening or a hole in something. A 'via' is an aperature in a PCB.
Artwork: Slang term used to describe the finished design of a printed circuit board. Usually this consists of gerbers.
Assembly: The process of placing components on a PCB.
Assembly Drawing: A drawing that is intended to be human readable, showing locations of components on the PCB and any other requirments that need to be followed during assembly.
ATE: Acronym that stands for 'automated tested envoirnment'. ATE's are helpful so a series of long tests can be perform repeatedly without the need for human help.
Auto-Route: A tool that usually accompanies PCB design software and has the capability of automatic / computer routing of traces on the PCB. It can greatly speed up the design of some PCB. It's not always desired on more complex designs that require extra attention to where some more critical nets are routed.
BGA: An acronym that for 'Ball Grid Array'. This is an integrated circuit thats connecting pins are small round balls of solder on the underside of the chip. The BGA is heated, usually in a oven, until these solder balls melt, connecting the chip to the PCB. A BGA is usefull for integrated circuits that have many pins for connectivity.
BOM: An acronym for 'bill of materials'. This is a list of items needed to build the product. It will contain ICs, resistors, capacitor and anything else that's needed.
CAD: An acronym for 'computer aided drafting. This is the process of creating something on a computer first, before the physical items is made.
CAM: Computer Aided Manufacturing.
Capture: Slang term used to describe the creation of schematics for a design or circuit.
Cathode: The negative "-" side of a device. This is opposite of positive or anode "+".
COB: An acronym for chip on board. This reffered to the actual silicon itself being attached directly to the PCB, instead of the silicon behing encapsulated inside of a chip package such as a BGA.
Differential Pair: A signal that consists of two traces or wires. The voltages of either wire is opposite that of it's pair. For example, One wire might be at +1 volt and the other will be at -1 volt. However, the pare does not need a ground as reference so that means one can be at +8volts and the other at +6 volts. The center would then be +7 volts. Differential signaling is usually reserved for very high speed signals.
Digital: A term used to describe a voltage level as being either zero "0" or one "1". It can also represent 'off' and 'on', or 'low' and 'high'. This is the opposite of 'analog'.
Diode: A device that conducts current in only one direction, when the anode is connected to a positive voltage in relation to the the cathod side of the device.
DIP: An acronym for dual in line package. This is a type of packaging that an integrated circuit can be in.
EMC: An acronym for electromagetic compatibility. This usually referrs to the compliance of a device in regard to electromagnetic radio interference. This is usually done on products intended to be mass produced so that a device will not create problem in other devices that rely on signal retrieved from the airwaves through an antenna.
Fabrication: A term used to describe the physical creation of a printed circuit board.
FlipChip: See COB.
Footprint: A term used to describe the actualy land pattern that a component will use to sit onto a PCB.
Gerbers: A file or file set that contains information that can be used to fabricate a printed circuit board. Sometimes refered to as CAM files (Computer Aided Manufacturing).
HASL: Hot Air Solder leveling. After a PCB is etched, the fabrication house will apply a thin layer of solder to the exposed copper left after SMOBC application. This helps with component assembly and keeps the copper from oxidizing from being exposed to the open air.
Integrated circuit (or IC): A device that contains an lot of 'integrated' components into a small silicon die. A very large amount of components can be placed into an IC.
Multimeter: An instrument usually used to measure voltages and currents as well as resistance.
Net: A 'wire' that connected multiple electronic points or 'pins' together. "VCC3.3" and "Clock" and "Data3" are all examples of nets.
Netlist: A list of nets. Usually this list is used to import information into another software package. For example; creating a netlist from a schematic capture tool, and importing it into a PCB layout software package.
Origin: Location " 0 x 0 " in the coordinate system for the PCB layout system. Knowing the origin is usefull for the assembly because all the component locations on the PCB are referenced from this origin. Usually in the botom left hand side of the PCB.
Panalize: Taking one board (in the form of gerber files), and place it into an array (more than one). A 2x2 array would be called "4-up" (industry slang). Panlization is helpful to speed the assembly process. Multiple boards can be assembly my computer aided manufacturing at one time. After assembly, the boards are then separated into the individual boards by means of 'rat-bites' or 'scoring'.
Passive Component: A device that doesn't have a power or ground pin to become usefull. A resistor, capacitor and inductor are all examples of passive parts.
PCB: See Printed Circuit Board .
PCB database: Usually a zip file containing everything needed for a PCB fabrication house to create the PCB. It usually contains gerbers and a readme.txt file for special instructions.
Plated Through Hole: A hole plated with metal after it has been drilled at the PCB fabrication house. A via is an example of a plated through hole.
Printed Circuit Board: A board with metal on the outside that has been etched away to form small wires and patterns for component placement and connectivity. The PCB usually has a non-conductive material in the center, with a think layer of copper on the outsides. This would be considered a 2-layer board. The PCB is then finished with a HASL and SMOBC finish.
PWB: Printed wiring board. The same meaning as PCB.
Rat Bite: A Rate Bite is a term used for the break-away section of the PCB, that enables is to be easily removed from the arrayed panel. Rate Bites or V-Scoring is used so that many PCBs can be made on the same panel, and later broken apart. Once broken apart, it apears as though a rat nibbled on the side of the board.
Rats Nest: straight lines used in a PCB layout software package used to represent unconnected, or unrouted traces on the PCB. The rats nest will show a straight line from the connection points that need to be routed. The term was derived from the apperance of the begining of a brand new layout project. "it's looks like a big ugly rats nest".
Reference Designator: The identifing letter and number that represents the component on the PCB or the schematic. "R24" and "U3" and "J6" are examples of reference designators.
Schematic: A line/symbol representation of an electronic design. The schematic will include all the components in the design in the form of symbols and show lines 'connected' the components together.
Silkscreen: Lettering/numbering on the top (and/or bottom) of a PCB. It will include reference designators, component outlines, and any other notes that the design needs to relay to the user of the PCB.
SMD: Surface Mount Device.
SMT: Surface Mount Technology.
SMOBC: Solder Mask Over Bare Copper - See Solder Mask.
Solder ball: The connecting pins on the underside of a BGA.
Solder Mask: A protective coating (usually green) on the PCB that keeps the copper traces protected from oxidation and solder bridging. The solder mask will have opening in places were components are to be attached (through hole or SMD components).
Tented Via: A via without the Solder Mask removed (the via is 'tented' ovre with a layer of solder mask).
Through Hole: Meaning a component has pins that need to go 'through' the PCB during assembly. The opposite of Surface mount.
Via: A plated drill hole that is used to get a trace/signal, to another layer in the PCB design.
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