Here is a very comprehensive glossary of both common and not so common
terms used in the computer industry..
After Receipt of Order.
Time interval between
the instant that a piece of information is requested from a memory device
and the instant the information is supplied by the memory
The area of the RAM that stores the bits. The array
consists of rows and columns, with a cell at each intersection that can
store a bit. The large rectangular section in the center of the die where
the memory is stored.
Ball Grid Array.
The amount of data that can be moved through a
particular interface in a given period of time, e.g. a 64-bit wide, 100
MHz SDRAM data bus has a bandwidth of 800 Megabytes per
A printed circuit board (PCB) that does not have any
components on it.
A circuit or system drawing concerned with major functions
and interconnections between functions.
The process of exercising an integrated circuit
at elevated voltage and temperature. This process accelerates failure
normally seen as "infant mortality" in a chip. (Those chips that would
fail early during actual usage will fail during burn-in. Those that pass
have a life expectancy much greater than that required for normal
An electronic traffic lane through which electrical
signals are carried through one chip to another chip. For example, the
address bus between an SDRAM and a DRAM controller takes the electrical
signals which define a certain address and transfers them to the SDRAM
Column-address-strobe. The signal which tells the
DRAM to accept the given address as a column-address. Used with RAS and a
row-address to select a bit within the DRAM.
Column Address Strobe Before Row Address
Strobe. A fast refresh technique in which the DRAM keeps track of the next
row it needs to refresh, thus simplifying what a system would have to do
to refresh the part.
Complementary Metal Oxide Semiconductor. A process
that uses both N- and P-channel devices in a complimentary fashion to
achieve small geometries and low power consumption.
The number of pulses emitted from a computer's clock in one
second; it determines the rate at which logical or arithmetic gating is
performed in a synchronous computer.
Part of the memory array. A bit can be stored
where a column and a row intersect.
One of the major units in a computer that
interprets and carries out the instructions in a program.
Dual In-line Package.
Dynamic Random Access Memory. A type of memory
component used to store information in a computer system. 'Dynamic' means
the DRAMs need a constant 'refresh' (pulse of current through all of the
memory cells) to keep the stored information. (See also RAM and
On boards: The date of preliminary release (the date that a
printed circuit boards are approved for fabrication.) On component: The
date of manufacture. In Test area: The code (on the part) showing the year
and work week the part was marked.
An individual rectangular pattern on a wafer that
contains circuitry to perform a specific function. The internal circuitry
is made of thousands of tiny electronic parts. 'Die' refers to a
semiconductor component or part that has not yet been packaged (also known
as 'IC' (Integrated Circuit) or 'chip').
The physical measurements of the die.
A computer feature that allows peripheral systems to
access the memory for both read and write operations without affecting the
state of the computer's central processor.
The process of preparing product for shipment in moisture
vapor barrier bags. This process includes tubed or reeled product and a
clay desiccant, and an HIC(Humidity Indicator Card), vacuum-sealed in a
moisture vapor barrier bag.
Type of RAM (Random Access Memory). To keep data
in the D(ynamic)RAM memory, this data needs to be 'refreshed' (recharged).
The electric charge fades out of a DRAM like air seeps out of a balloon.
Because of this change, it is called 'Dynamic.'
Electrically Erasable PROM.
Electrically Erasable Programmable Logic Device. A
CMOS PLD made by using EEPROM technology. It can be erased and
Electrically Erasable, PROgrammable, read-only
Memory chip. EEPROMs differ from DRAMs in that the memory stays in even if
electrical power is lost. Also, the memory can be erased and
Electrostatic discharge. The dissipation of
electricity. ESD can easily destroy the semiconductor
The process of applying a cured-plastic
protective housing to components. A mold compound. An Assembly
A process using a chemical bath (wet etch) or a
plasma (dry etch) that removes unwanted substances from the wafer
A local area network allowing several computers
to transfer data on a communications cable.
Description of the rate at which parts fail, usually expressed
as percent per 1,000,000
Material that fails various tests within the component
Flash memory is a non-volatile memory device that retains
its data when the power is removed. The device is similar to EPROM with
the exception that it can be electrically erased, whereas an EPROM must be
exposed to ultra-violet light to erase.
The computer and display used at each die attach machine to
display the map and/or messages pertaining to the map or the
A Teflon Polyurethane wafer holder used to
transport individual wafers. Flatpacks can be stacked to carry and protect
several wafers at a time.
A flat, rectangular IC package type with leads
sticking out from the sides of the package.
Indicates Goldstar as manufacturer (see also
Indicates hitachi as manufacturer.
A structure, attached to or part of a semiconductor device
that serves the purpose of dissipating heat to the surrounding
environment; usually metallic. Some packages serve as heat
Integrated Circuit. A tiny complex of electronic
components and their connections that is produced in or on a small slice
of material (as silicon).
Integrated Device Technology.
Indicates Lucky Goldstar as
The metal extensions from an IC package or discrete
component that connects the component to the PCB. The leg or contact point
of the component that is either physically soldered to a PC board or
placed within a socket for connection.
A metal structure that is part of the device.
The die is attached to the leadframe.
Leads or Legs: The official name for the metal
'feet' on an IC. Also called 'pins.' The part of the lead assembly that is
formed after a portion of the lead frame is cut away. The part's
connection to the outside world.
A circuit that produces a voltage output approximately
proportional to the input voltage, generally over a limited range of
A pin in the mold which locates the leadframe in the correct
position on the mold for processing.
An integrated circuit which provides a fixed set of output
signals according to the signals present at the input.
Several individual device functions on an integrated circuit
Amount of memory equal to 1,048,576 bits of
information. (Abbreviated Mb.)
Millions of Instructions Per Second. This
measurement is generally used when describing the speed of computer
Indicates Mitsubishi as manufacturer.
Metal-Oxide-Semiconductor. Layers used to create a
semiconductor circuit. A thin insulating layer of oxide is deposited on
the surface of the wafer. Then a highly conductive layer of tungsten
silicide is placed over the top of the oxide dielectric.
One million binary pieces (bits) of
The amount of memory in an IC and how it is accessed.
Also, a code on the lot traveler used to indicate the IC's memory
configuration (e.g., 1M1 = 1 Meg x 1, 4M4 = 4 Meg x 4,
Minimum amount of time required for a memory to complete a
cycle such as read, write, read/write, or
Cache Data SRAM: quick-access chip. DRAM dynamic random
access memory. EPROM: erasable, programmable, read-only memory. PROM:
programmable, read-only memory. RAM: random access memory. ROM: read-only
memory (permanent memory that cannot be changed). SRAM: static random
Contained on one chip or substrate, as a
microprocessor system including not only the logic but also memory or
N-channel Metal Oxide Semiconductor. This pertains
to MOS devices constructed on a P-type substrate in which electrons flow
between N-type source and drain contacts. NMOS devices are typically two
to three times faster than PMOS devices.
nanosecond (ns). One billionth of a second; used to
measure the speed of the parts (e.g., -07 nanoseconds).
Non-Volatile Random Access Memory.
Literal: One-billionth (10 to the -9). Diffusion: A
tool used to measure the thickness of a film on a wafer.
One billionth of a meter.
One billionth of a second. Light travels
approximately 8 inches in 1 nanosecond.
A memory that retains information if
power is removed and then reapplied.
Software controlling the overall operation of a multipurpose
computer system, including such tasks as memory allocation, input and
output distribution, interrupt processing, and job
Programmable Array Logic. A device that can be
programmed to do certain logic functions. Then a fuse inside of the device
can be blown so the programmed information can never be changed. Sometimes
called a PLD (Programmable Logic Device) Language.
Printed Circuit Board; board upon which there are
layers of printed circuits where DRAMs can be attached with solder so that
memory can be accessed.
Pin Grid Array.
Programmable Logic Array. An array of logic elements
that can be programmed to perform a specific logic function. It can be as
simple as a gate or as complex as a ROM and can be programmed (often by
mask programming) so that a given input combination produces a known
Programmable Logic Devices. Devices with 10-100 times
higher level of integration than a TTL; called programmable because they
can be customized in software rather than in hardware.
Plastic Quad Flat Pack. A square, flat package with
18-52 gullwing leads located around all four sides of the
Mode in which if RAS is kept low and the DRAM is given a
column-address without being given a new row-address, the chip will
remember which row it was on the last time and automatically stay on that
row. It is like saying that all the bits along one row are all on the same
'page,' and the part will assume the same page is intended until a
different page is specified.
The number used to identify the family, capacity, and
special characteristics of the part (e.g., 4C4001: 4 = DRAM, C = CMOS,
4001 = memory density (1 million bits) and how it is accessed (4 access
A device incapable of current gain or switching such as a
resistor or capacitor.
The metal extensions from an IC package or discrete
component that connects the component to the PCB.
A PCB with components.
To turn the system's power OFF.
To turn the system's power ON.
QFP: A flat, rectangular, integrated circuit with its leads
projecting from all four sides of the package without
Row-Address-Strobe: the signal that tells the DRAM to
accept the given address as a row-address. Used with CAS and a
column-address to select a bit within the DRAM.
Reduced Instruction Set Computing. The design
methodology is usually associated with microprocessors. RISC chips use
simpler instructions, or commands, than CISC chips. However, they need to
use more steps to perform many functions that CISC chips perform in one
step. SPARC and MIPS chips are based on RISC.
Returned Material Authorization; required if a
customer desires to return products. Also refers to parts that have been
returned from a customer.
The amount of time required for the output data to become
valid once the read and address inputs have been enabled; generally called
Part of the RAM array; a bit can be stored where a
column and a row intersect.
The number of the row where a particular bit is
Describes how many rows are on a wafer map in
the X direction. (X = left to right. Y = top to bottom).
Synchronous Dynamic Random-Access Memory. Delivers
bursts of data at very high speeds using a synchronous
Synchronous Graphic Random-Access
Single In-line Memory Module: a high-density DRAM
package alternative consisting of several PLCCs connected to a single
printed circuit board. A small PCB designed to mount in a socket on a
larger PCB providing a large memory upgrade in a small space. One of the
products of Micron.
Single In line Package. A component or module that
has one row of leads along one side. Many resistors come in SIP
Small Outline J-lead package. A rectangular package
with leads sticking out of the side of the package. The leads are formed
in a J-bend profile, bending underneath and towards the bottom of the
package. Lead counts range from 20 to 44 leads.
(Static Random Access Memory) An integrated circuit
similar to a DRAM (Dynamic Random Access Memory) with the exception that
the memory does not need to be refreshed.
An element, such as silicon, that has
intermediate in electrical conductivity between conductors and insulators,
which conduction takes place by means of holes and
A reduction in die (chip) size. A reduction in the
size of the circuit design resulting in smaller die sizes that increases
the number of possible die per wafer.
The time it takes the RAM to put information into
its memory or get information out of its memory. It is measured from the
time that an address and proper control signals are given, until the
information is stored or placed in the device's output(s).
Our coding for the speed that the stored information in the
part can be retrieved by a computer. For DRAMs, a -5 is 50 nanoseconds, a
-6 is 60 nanoseconds, a -7 is 70 nanoseconds, etc. For SRAMs, a -10 is 10
Unlike volatile memory, static memory retains its contents even
when the main current is turned off. The trickle of electricity from a
battery is enough to refresh it.
An input that allows parallel data to be entered a
The actual structural material on which
semiconductor devices are fabricated, whether passive or active. The term
applies to any supportive material, such as the materials used in the
fabrication of printed circuits.
A J-leaded or Gullwing package (DJ,
TG, RG, G, EJ, etc.) that can be mounted directly on the surface of P.C.
Boards (as opposed to through-hole packages).
Indicates Texas Instruments as
Indicates Toshiba as manufacturer.
Thin Small Outline Package. It is thinner and
slightly smaller than an SOJ and with gullwing-shaped leads. Our TSOP is
1.2mm in height. Height distinguishes the TSOP from the SSOP. A thin,
rectangular package with leads sticking out the sides of the package. Lead
counts range from 20 to 40 leads.
An electrical process every product goes through
which tests the parts for parametric, speed, and functional
A semiconductor device that uses a stream of
charge carriers to produce active electronic effects.
Video Random-Access Memory.
Indicates Western Digital as
Write-Enable; WE must be pulsed low when data is
written to the chip.
Time expended from the moment data is entered for storage to
the time it is actually stored.