Home
About Us
Bank details
Contact us
See our RMA Policy
Support Links
Glossary terms

Here is a very comprehensive glossary of both common and not so common terms used in the computer industry..

A

ARO
After Receipt of Order.

Access time
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 device.

Array
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.

B

BGA
Ball Grid Array.

Bandwidth
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 second.

Bare board
A printed circuit board (PCB) that does not have any components on it.

Block diagram
A circuit or system drawing concerned with major functions and interconnections between functions.

Burn-in
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 usage.)

Bus
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 memory.

C

CAS
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.

CAS-B4-RAS
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.

CMOS
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.

Clock rate
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.

Column
Part of the memory array. A bit can be stored where a column and a row intersect.

Controller
One of the major units in a computer that interprets and carries out the instructions in a program.

D

DIP
Dual In-line Package.

DRAM
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 SRAM.)

Date code
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.

Die
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').

Die size
The physical measurements of the die.

Direct memory access
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.

Dry pack
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.

Dynamic
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.'

E

E2PROM
Electrically Erasable PROM.

EEPLD
Electrically Erasable Programmable Logic Device. A CMOS PLD made by using EEPROM technology. It can be erased and reprogrammed.

EEPROM
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 reprogrammed.

EPROM
Erasable PROM.

ESD
Electrostatic discharge. The dissipation of electricity. ESD can easily destroy the semiconductor product.

Encapsulation
The process of applying a cured-plastic protective housing to components. A mold compound. An Assembly step.

Etch
A process using a chemical bath (wet etch) or a plasma (dry etch) that removes unwanted substances from the wafer surface.

Ethernet
A local area network allowing several computers to transfer data on a communications cable.

F

Failure rate
Description of the rate at which parts fail, usually expressed as percent per 1,000,000

Fall out
Material that fails various tests within the component manufacturing process.

Flash memory
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.

Flat panel display
The computer and display used at each die attach machine to display the map and/or messages pertaining to the map or the lot.

Flatpack
A Teflon Polyurethane wafer holder used to transport individual wafers. Flatpacks can be stacked to carry and protect several wafers at a time.

Flatpack
A flat, rectangular IC package type with leads sticking out from the sides of the package.

G

GS
Indicates Goldstar as manufacturer (see also LGS)

H

HIT
Indicates hitachi as manufacturer.

Heat sink
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 sinks.

I

IC
Integrated Circuit. A tiny complex of electronic components and their connections that is produced in or on a small slice of material (as silicon).

IDT
Integrated Device Technology.

J

K

L

LGS
Indicates Lucky Goldstar as manufacturer.

Lead
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.

Leadframe
A metal structure that is part of the device. The die is attached to the leadframe.

Leads
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.

Linear circuit
A circuit that produces a voltage output approximately proportional to the input voltage, generally over a limited range of voltage frequency.

Locator pin
A pin in the mold which locates the leadframe in the correct position on the mold for processing.

Logic circuit
An integrated circuit which provides a fixed set of output signals according to the signals present at the input.

Logic gate
Several individual device functions on an integrated circuit chip.

M

MEG
Amount of memory equal to 1,048,576 bits of information. (Abbreviated Mb.)

MIPS
Millions of Instructions Per Second. This measurement is generally used when describing the speed of computer systems.

MIT
Indicates Mitsubishi as manufacturer.

MOS
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.

Megabit
One million binary pieces (bits) of information.

Memory configuration
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, etc.).

Memory cycle
Minimum amount of time required for a memory to complete a cycle such as read, write, read/write, or read/modify/write.

Memory types
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 access memory.

Monolithic
Contained on one chip or substrate, as a microprocessor system including not only the logic but also memory or input/output circuits.

N

NMOS
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.

NS
nanosecond (ns). One billionth of a second; used to measure the speed of the parts (e.g., -07 nanoseconds).

NVRAM
Non-Volatile Random Access Memory.

Nano
Literal: One-billionth (10 to the -9). Diffusion: A tool used to measure the thickness of a film on a wafer.

Nanometer
One billionth of a meter.

Nanosecond
One billionth of a second. Light travels approximately 8 inches in 1 nanosecond.

Nonvolatile memory
A memory that retains information if power is removed and then reapplied.

0

Operating system
Software controlling the overall operation of a multipurpose computer system, including such tasks as memory allocation, input and output distribution, interrupt processing, and job scheduling.

P

PAL
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.

PCB
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.

PGA
Pin Grid Array.

PLA
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 output function.

PLD
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.

PQFP
Plastic Quad Flat Pack. A square, flat package with 18-52 gullwing leads located around all four sides of the package.

Page mode
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.

Part number
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 lines).

Passive device
A device incapable of current gain or switching such as a resistor or capacitor.

Pin
The metal extensions from an IC package or discrete component that connects the component to the PCB.

Populated board
A PCB with components.

Power down
To turn the system's power OFF.

Power up
To turn the system's power ON.

Q

Quad flat pack
QFP: A flat, rectangular, integrated circuit with its leads projecting from all four sides of the package without radius.

R

RAS
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.

RISC
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.

RMA
Returned Material Authorization; required if a customer desires to return products. Also refers to parts that have been returned from a customer.

Read time
The amount of time required for the output data to become valid once the read and address inputs have been enabled; generally called access time.

Row
Part of the RAM array; a bit can be stored where a column and a row intersect.

Row address
The number of the row where a particular bit is stored.

Row/columns
Describes how many rows are on a wafer map in the X direction. (X = left to right. Y = top to bottom).

S

SDRAM
Synchronous Dynamic Random-Access Memory. Delivers bursts of data at very high speeds using a synchronous interface.

SGRAM
Synchronous Graphic Random-Access Memory.

SIMM
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.

SIP
Single In line Package. A component or module that has one row of leads along one side. Many resistors come in SIP form.

SOJ
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.

SRAM
(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.

Semiconductor
An element, such as silicon, that has intermediate in electrical conductivity between conductors and insulators, which conduction takes place by means of holes and electrons.

Shrink
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.

Speed
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).

Speed grade
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 nanoseconds, etc.

Static RAM
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.

Strobe
An input that allows parallel data to be entered a synchronously.

Substrate
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.

Surface-mount package
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).

T

TI
Indicates Texas Instruments as manufacturer

TOSH
Indicates Toshiba as manufacturer.

TSOP
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.

Test
An electrical process every product goes through which tests the parts for parametric, speed, and functional failures.

Transistor
A semiconductor device that uses a stream of charge carriers to produce active electronic effects.

U

V

VRAM
Video Random-Access Memory.

W

WD
Indicates Western Digital as manufacturer.

WE
Write-Enable; WE must be pulsed low when data is written to the chip.

Write time
Time expended from the moment data is entered for storage to the time it is actually stored.

X

Y

Z

ZIP
Zig-zag In-line Package.