F
Failure rate
Description of the rate at which parts fail, usually expressed as percent per 1,000,000.
Fake Parity
Unlike odd and even parity, fake parity is not capable of detecting an invalid data bit. It was designed to artificially 'satisfy' a parity-enabled computer without actually checking the data for errors. Fake parity attaches a bit to each byte of data just like odd and even parity protocols. The difference is that fake parity simply adds the correct parity bit as the data is sent to the CPU instead of attaching it before the data is stored to memory, and recalculating it before the byte passes to the CPU.
Fall out
Material that fails various tests within the component manufacturing process.
FBGA
Fine BGA is a ball grid array package with a fine pitch ball arrangement on the underside of the package (larger than CSP).
FIT
Failures In Time.
FSB
Front Side Bus is the data channel connecting the processor, chipset, DRAM, and AGP socket. FSB is described in terms of its width in bits and it's speed in MHz.
Flag
In computing: A status bit that causes some indication of the state or condition of the processing unit.
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. Flash memory does not need a constant power supply to retain its data and it offers extremely fast access times, low power consumption, and relative immunity to severe shock or vibration. These qualities combined with its compact size, make it perfect for portable devices like scanners digital cameras, cell phones, pagers, hand-helds and printers. Flash chips have a lifespan limited to 100,000 write cycles, which means flash will never replace main memory in computers.
Flatpack(1)
A Teflon Polyurethane wafer holder used to transport individual wafers. Flatpacks can be stacked to carry and protect several wafers at a time.
Flatpack(2)
A flat, rectangular IC package type with leads sticking out from the sides of the package.
Flip-flop
A circuit with two stable states that can be changed from one to the other. Flip-flops are the storage element in most of the SRAMs.
Floating
Pertaining to the condition of a device or circuit that is neither grounded nor connected to any potential. (Potential is voltage course or current course).
Floating gate
In Silicon Gate MOS technology: a gate that is not directly connected to the rest of the circuit. Used in EEPROMs.
FPM
Fast Page Mode - A common DRAM data-access scheme. Accessing DRAM is similar to finding information in a book. First, you turn to a particular page, then you select information from the page. Fast-page mode enables the CPU to access new data in half the normal access time, as long as it is on the same page as the previous request. This feature is used to support faster sequential access to DRAM by allowing any number of accesses to the currently open row to be made after supplying the row address just once.
Frequency converter
A device or system that can change the frequency of an alternating current, whether or not it changes the voltage or phase.
G
Gigabit
Approximately 1 billion bits: 1 bit x 1,024 (that is, 1,073,741,824 bits) Or exactly 2^30 bits.
Gigabyte, GB
A unit of measurement approximately equal to 1024 megabytes. Computer components process data in bytes or multiples of bytes such as kilobytes (~1,000 bytes), megabytes (~1 million bytes), and gigabytes (~ 1 billion bytes).
GND
Ground.
Gold wire
The wire used to make a physical connection from the device to the leadframe.
H
Hard failure
Die that fail functionality testing. These failures have a visual defect 99 percent time, such as poly or metal bridging, missing geometries or layers, particles or contaminates.
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.
HPM
Hyper Page Mode also known as
HTOL
High Temperature Operating Life.
I
I/O port
Connection to a CPU that is configured or programmed to provide data path between the CPU and external devices such as a keyboard, display, or reader; it may be an input port or an output port, or it may be bi-directional.
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).
ICE
In Circuit Emulator.
ID
Identification Detect. Pins present on DIMMs to provide information to the system using the module.
IEEE-488
Standard set by IEEE (
Infant Mortality
Used to describe the occurrence of premature failures at a higher than normal rate.
Intelligent
A burn-in process whereby electrical functionality of the parts is continuously or periodically monitored and recorded under various voltages, temperatures, and refresh conditions during the burn-in process. This continuous or periodic monitoring of the functionality of each IC allows intelligent decisions to be made.
IO CARD
A PCB that interfaces between the computer and an interface board.
IR
Current x Resistance = Voltage. Also an abbreviation for Infrared.
ISD
An amorphous, doped polysilicon used as an underlying layer for the HSG poly to increase conductivity.
ISO 9
International Standards Organization.
J
JEDEC
Joint Electron Device Engineering Council - the group that establishes the industry standards for memory operation, features and packaging.
K
Keys
Notches on a memory module that prevent it from being installed incorrectly or into an incompatible system.
Kilobit Approximately one thousand bits: 1 bit x 210 (that is, 1,024 bits).
Kilobyte, KB
A unit of measurement approximately equal to 1024 bytes. Computer components process data in bytes or multiples of bytes such as kilobytes (~1,000 bytes), megabytes (~1 million bytes), and gigabytes (~ 1 billion bytes).
L
L1 cache
Level 1 cache. A small cache integrated in processor that provides a small working space for quick access to the most recently used data.
L2 cache
A specialized memory unit that enhances DRAM performance by providing the CPU with data at speeds ten times faster than DRAM. The L2 cache is comprised of Static RAM (SRAM), a high-speed RAM that does not need to be refreshed to retain its data. Most computers have two different memory caches; L1 cache, located on the CPU, and L2 cache, located between the CPU and DRAM. L1 cache is faster than L2, and is the first place the CPU looks for its data. If data is not found in L1 cache, the search continues to the L2 cache and then to DRAM. In early processors, the L2 cache was not integrated into the processor but rather built into the motherboard, and was in some cases upgradeable.
Laser scribe
Process which uses a YAG (Yittrium-aluminum-Garnet) laser to melt the silicon in a dot matrix to form wafer scribe numbers.
Latch
Circuit element that stores a given value on its output until told to store a different value.
Latch up
An undesired phenomenon in an integrated circuit whereby a circuit locks in a certain state and will not change.
Latch voltage
The effective input voltage at which a flip-flop changes states.
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.
Leakage
Undesirable conductive paths in components, subsystems, and systems; also the current through such paths.
Life testing
Accelerated testing of electronic components to establish their field reliability.
Linear circuit
A circuit that produces a voltage output approximately proportional to the input voltage, generally over a limited range of voltage frequency.
Linear regulator
Power supply design in which the voltage is held constant by dissipating 50% of the input voltage times and output current as a margin.
Linear selection
A method of selecting memory or input/output devices that dedicates one address line per chip selection; results in overlapping or noncontiguous memory; used because it is the cheapest method of selection.
Locator pin
A pin in the mold which locates the leadframe in the correct position on the mold for processing.
Logic Board
(See motherboard)
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.
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