-M-

Manhattan Distance ~ The distance between two points measured along axes at right angles.  Also known as rectilinear distance.

Matched Impedance ~ A design technique in which the output impedance of the driving source is equal to the input impedance of the load in order to reduce reflections and to transfer maximum power.

Maximum Power Transfer Theory ~ Maximum power is transferred to the load when the impedance of the driving source is equal to the impedance of the load, a matched impedance condition.

Megahertz (MHz) ~ One thousand Hertz, or cycles per second.

Metal Oxide Field Effect Transistor (MOSFET) ~ This is a transistor with a source and drain region kept apart by a gate.  A forward bias voltage applied to the gate controls the flow of electrons from the source to the drain.

Meter ~ The standard unit of length in the metric system.

Micrometer ~ One millionth of a meter or 1/1,000,000 meters.

Microfarad (uF) ~ A common unit of electric capacitance equal to 10-6 farad.

Micron (uM) ~ One millionth of a meter or 1/1,000,000 meters.

Microvia ~ A very small hole drilled or etched into a printed circuit board for continuing connectivity to a different layer. It is a design technique aimed at reducing substrate (product) size. A microvia is a via less than 150um (4mils) in diameter, about a half the size of common via, and normally blind.  Laser drilling make microvias at 500X the speed of mechanical drills.

Mil ~ One thousandth of an inch. (1 mil = 25.4 cm = .0254 mm)

Millimeter ~ One thousandth of an meter. ( 1 mm = 39.37 mils)

Mixed Technology ~ Describes the assembly process used when through-hole, surface mount, and other mounting technologies are used on the same printed circuit board.

Multi-Chip Module (MCM) ~ A modular package with both active and passive devices in one package.  It may contain multiple silicon die(s) directly bonded to the printed circuit board

-N-

Nanometer ~ One billionth of a meter or 1/1,000,000,000 meters

Netlist ~ A list to groups of two or more points in a circuit design that are electrically common.

Nibble ~ Four bits or half a byte.

Nickel Metal Hydride (NiMH) ~ A type of rechargeable battery composed of metal alloys and Nickel.  NiMH cells provide extended use lifetimes and are safer to the environment.

Node ~  A single computer on a network or a predetermined analysis point in an electrical circuit.

-O-

Ohm ~ Standard unit for measuring electrical resistance.

Ohmmeter ~ Device used for measuring resistance.

Op-Amp ~  An operational amplifier originally used in analog computers.  They require positive and negative voltage sources and contain an inverting input, a non-inverting input and an output.  Op-amps may be configured to operated many different ways.

Original Equipment Manufacturer (OEM) ~ This acronym is used to denote equipment that is sold to other companies or resellers for integration into systems.

Orthogonal ~ This term is used to describe two or more things that are independent of each other. Also, it is a mathematical term that refers to vectors that meet at right angles.

-P-

Parasitic ~ The inherent capacitance, inductance, and resistance of a trace or wire.

Pad ~ A rectangular or circular shaped conductive pattern used as a termination area on a printed circuit board.

Panel ~ An array of usually identical but separate printed circuit boards fabricated on a single substrate.

Passive Component ~ An electronic component which adds no gain to the signal, such as resistors, capacitors, inductors, diodes, etc...

Period ~ The time in seconds that it takes for an alternating signal to complete one cycle or the inverse of the frequency.

Photolithography ~ The photographic process used to transfer circuit patterns onto a semiconductor wafer. This is done by projecting light through a patterned reticule, onto a silicon wafer covered with a photo-resist.

Pin Grid Array (PGA) ~ This is a form of packaged IC with a group of through-hole pins in arranged in concentric rectangles.

Pitch ~ The center to center spacing between pads, rows, bumps, pins, posts, leads, etc...

Photo-resist ~ Light-sensitive liquid used to resist chemical processes such as etching.

Plating, Additive ~ A process in which the conductive, resistive, and insulating materials are successively added to define traces, pads, and elements.

Plating, Electroless ~ Plating as the result of chemical action without any external electric current.

Plating, Electrolytic ~ Plating deposited by application of electrical current.

Polytetrafluoroethylene (PTFE) ~ Teflon based printed circuit board material used for high-speed applications.

Pogo ~ A brand name for a spring loaded test probe.

Potentiometer ~ Adjustable resistor.

Pre-preg ~ Pre-impregnated materials are a combination of fiber and resin to create a material that is stronger than either of its constituents alone.

Primary Side ~ Reference to the top side or majority populated or most complex side of a printed circuit board.

Printed Circuit Assembly ~ This refers to the printed circuit board after it is assembled with electronic components.

Printed Circuit Board (PCB) ~ This refers to the normally green plastic board that is imprinted with one or more layers of circuitry.

Printed Wiring Board (PWB) ~ This refers to the normally green plastic board that is imprinted with one or more layers of circuitry. Typically this is the military name for a printed circuit board.

 

These definitions were compiled from the internet and CADKraft Engineering assumes no liability in their accuracy nor their completeness.