Welcome to the electronics glossary in our library!

The following glossary entries were abstracted from the book, Bebop to the Boolean Boogie (An Unconventional Guide to Electronics), with the kind permission of LLH Technology Publishing, Eagle Rock, VA, USA                          ( to return to the main glossary.)

The proprietary name intended to reflect designs realized in virtual hardware. Derived from it's similarity to the concept of "Cache Memory".

A small, high-speed, memory (usually SRAM) used to buffer the central processing unit from any slower, lower cost memory devices such as DRAM. The high-speed cache memory is used to store active data( ), while the bulk of the data resides in the slower memory.

In a mathematical context this term is taken to mean a generic or basic representation. Canonical forms provide the means to compare two expressions without falling into the trap of trying to compare "apples" with "oranges".

A measure of the ability of two adjacent conductors separated by an insulator to hold a charge when a voltage differential is applied between them. Capacitance is measured in units of Farads.

A substance that initiates a chemical reaction under different conditions (such as lower temperatures) than would otherwise be possible. The catalyst itself remains unchanged at the end of the reaction.

The collective name for the set of logic functions defined by the manufacturer of an application-specific integrated circuit. The designer decides which types of cells should be realized and connected together to make the device perform its desired function.

The "brain" of a computer where all the number-crunching is performed.

An inorganic, nonmetallic material, such as alumina, beryllia, steatite, or forsterite, which is fired at a high temperature and is often used in electronics as a substrate or to create component packages.

A packaging technology similar to a pad grid array, in which a device's external connections are arranged as an array of conducting pads on the base of the package. However, in the case of a column grid array, small columns of solder are attached to the conducting pads.

Refers to a slice of quartz or similar material into which three-dimensional patterns are cut using a laser. The angles of the patterns cut into the quartz are precisely calculated for use in the optical communication strategy known as holographic interconnect. All of these calculations are performed by a computer, and the laser used to cut the three-dimensional patterns into the quartz is also controlled by a computer. Thus, the slice of quartz is referred to a computer-generated hologram.

(1)The area between two arrays of basic cells in a channeled gate array. (2)The gap between the source and drain regions in a MOS transistor.

Application-specific integrated circuit organized as arrays of basic cells. The areas between the arrays are known as channels.

Application-specific integrated circuit organized as a single large array of basic cells. May also be referred to as a "sea of cells" or a "sea of gates" device.

The final cyclic-redundancy-check value stored in a linear feedback shift register (or software equivalent). Also known as a "signature" in the guided-probe variant of functional test.

In the case of a chemically-amplified resist, the application of a relatively small quantity of ultraviolet light stimulates the formation of chemicals in the resist which accelerates the degrading process. This reduces the amount of ultraviolet light which is required to degrade the resist and allows the creation of finer features with improved accuracy.

A process for growing thin films on a substrate, in which a gas containing the required molecules is converted into a plasma by heating it to extremely high temperatures using microwaves. The plasma carries atoms to the surface of the substrate where they are attracted to the crystalline structure of the substrate. This underlying structure acts as a template. The new atoms continue to develop the structure to build up a layer on the substrate's surface.

A process similar to chemical vapor deposition (CVD) but, in this case, the process commences by placing a crystalline powder of the required substance in a mold. Additionally, thin posts, or columns, can be pre-formed in the mold, and the powder can be deposited around them. When exposed to the same plasma as used in the CVD technique, the powder coalesces into a polycrystalline mass. After the CVI process has been performed, the posts can be dissolved leaving holes through the crystal for use in creating vias. CVI processes can produce layers twice the thickness of those obtained using CVD techniques at a fraction of the cost.

Popular name for an integrated circuit.

A process in which unpackaged integrated circuits are physically and electrically attached to a circuit board, and are then encapsulated with a "glob" of protective material such as epoxy.

A process in which unpackaged integrated circuits are mounted on top of each other. Each die is very thin and it is possible to have over a hundred die forming a 3D cube.

Similar to chip-on-board (COC), except that the unpackaged integrated circuits are attached to a flexible printed circuit.

The generic name for a wide variety of interconnection techniques, which include rigid, flexible, and rigid-flex boards in single-sided, double-sided, multilayer, and discrete wired configurations.

Logic gates constructed using both NMOS and PMOS transistors connected in a complementary manner.

A conductor in the form of a central wire surrounded first by a dielectric (insulating) layer, and then by a conducting tube which serves to shield the central wire from external interference.

A process in which unpackaged integrated circuits are physically and electrically attached to a circuit board, and are then encapsulated with a "glob" of protective material such as epoxy.

A process in which unpackaged integrated circuits are mounted on top of each other. Each die is very thin and it is possible to have over a hundred die forming a 3D cube.

Defines the amount a material expands and contracts due to changes in temperature. If materials with different coefficients of thermal expansion are bonded together, changes in temperature will cause shear forces at the interface between them.

Similar to chip-on-board (COC), except that the unpackaged integrated circuits are attached to a flexible printed circuit.

A substrate formed from multiple layers of "green" ceramic that are bonded together and fired at the same time.

A packaging technology similar to a pad grid array, in which a device's external connections are arranged as an array of conducting pads on the base of the package. However, in the case of a column grid array, small columns of solder are attached to the conducting pads.

A digital function whose output value is directly related to the current combination of values on its inputs. Also known as combinational.

A digital function whose output value is directly related to the current combination of values on its inputs. Also known as combinatorial.

Algebraic rules that state that the order in which variables are specified will not affect the result of an operation; for example, a & b = b & a.

A logic function that compares two binary values, and outputs the results in terms of binary signals representing less-than and/or equal-to and/or greater-than.

A technique used to create portions of a standard cell application-specific integrated circuit. The masks used to create components and interconnections are directly generated from Boolean representations using a silicon compiler. May also be used to create data-path functions and memory functions.

Refers to a function with two outputs carrying complementary logical values. One output is referred to as the true output and the other as the complementary output.

Rules in Boolean Algebra derived from the combination of a single variable with the inverse of itself.

A device that contains a number of PLA or PAL functions sharing a common programmable interconnection matrix.

Refers to a slice of quartz or similar material into which three-dimensional patterns are cut using a laser. The angles of the patterns cut into the quartz are precisely calculated for use in the optical communication strategy known as holographic interconnect. All of these calculations are performed by a computer, and the laser used to cut the three-dimensional patterns into the quartz is also controlled by a computer. Thus, the slice of quartz is referred to a computer-generated hologram.

There are many different types of computer viruses but, for the purposes of this book, a computer virus may be defined as a self-replicating program released into a computer system for a number of purposes. These purposes range from the simply mischievous, such as displaying humorous or annoying messages, to the downright nefarious, such as corrupting data or destroying (or subverting) the operating system.

A technique in which tracks are screen printed directly onto the surface of a circuit board using a conductive ink.

Propositions combined with an AND operator; for example, "You have a parrot on your head AND you have a fish in your ear." The result of a conjunction is true if all the propositions comprising that conjunction are true.

A product whose function may be customized once or a very few times (see also Reconfigurable Hardware, Remotely Reconfigurable Hardware, Dynamically Reconfigurable Hardware, and Virtual Hardware).

A device that contains a number of PLA or PAL functions sharing a common programmable interconnection matrix.

The "brain" of a computer where all the number-crunching is performed.

A calculation used to detect errors in data communications, typically performed using a linear feedback shift register. Similar calculations may be used for a variety of other purposes such as data compression.

An alternative and possibly more accurate name for an ASIC, but this term is rarely used in the industry and shows little indication of finding favor with the masses.

To harden a material using heat, ultraviolet light, or some other process.

Refers to a material that has been hardened using heat, ultraviolet light, or some other process.

An alternative and possibly more accurate name for an ASIC, but this term is rarely used in the industry and shows little indication of finding favor with the masses.

A process for growing thin films on a substrate, in which a gas containing the required molecules is converted into a plasma by heating it to extremely high temperatures using microwaves. The plasma carries atoms to the surface of the substrate where they are attracted to the crystalline structure of the substrate. This underlying structure acts as a template. The new atoms continue to develop the structure to build up a layer on the substrate's surface.

A process similar to chemical vapor deposition (CVD) but, in this case, the process commences by placing a crystalline powder of the required substance in a mold. Additionally, thin posts, or columns, can be pre-formed in the mold, and the powder can be deposited around them. When exposed to the same plasma as used in the CVD technique, the powder coalesces into a polycrystalline mass. After the CVI process has been performed, the posts can be dissolved leaving holes through the crystal for use in creating vias. CVI processes can produce layers twice the thickness of those obtained using CVD techniques at a fraction of the cost.

A calculation used to detect errors in data communications, typically performed using a linear feedback shift register. Similar calculations may be used for a variety of other purposes such as data compression.

Copyright Information