| Fan-Out
Via |
In the case of surface mount
devices attached to double-sided or multilayer boards, each component
pad is usually connected by a short length of track to a via which forms
a link to other conducting layers, and this via is known as a fan-out
via. The term fan-out via is generally also taken to include any vias
that fall inside the device's footprint (under the body of the device).
Some designers attempt to differentiate these vias from those that fall
outside the device's footprint by referring to them as fan-in vias, but
this is not an industry-standard term. |
| a |
| Femto |
Unit qualifier (symbol = f)
representing one thousandth of one millionth of one millionth, or
10-15. For example, 3fS stands for 3 x 10-15
seconds. |
| a |
| FET
(Field-Effect Transistor) |
A transistor whose
control, or gate, signal creates an electro-magnetic field which turns
the transistor ON or OFF. |
| a |
| Field-Effect
Transistor (FET) |
A transistor whose control, or
gate, signal creates an electro-magnetic field which turns the
transistor ON or OFF. |
| a |
| Face-Surface
Mirror |
A mirror in which the
reflective coating is located on the face of the mirror, and not behind
it as would be the case in the mirror you look into when you shave or
apply your makeup (or both depending on how liberated you
are). |
| a |
| Falling-Edge |
A transition from a logic 1 to
a logic 0. Also known as a negative edge. |
| a |
| Fan-In and
Fan-Out Vias |
In the case of surface
mount devices attached to double-sided or multilayer boards, each
component pad is usually connected by a short length of track to a via
which forms a link to other conducting layers, and this via is known as
a fan-out via. The term fan-out via is generally
also taken to include any vias that fall inside the device’s footprint
(under the body of the device). Some designers attempt to differentiate
these vias from those that fall outside the device’s footprint by
referring to them as fan-in vias, but this is not an
industry-standard term. |
| a |
| Field-Programmable Gate
Array (FPGA) |
A programmable logic
device which is more versatile than traditional programmable devices
such as PALs and PLAs, but less versatile than an application-specific
integrated circuit. Some field-programmable gate arrays use fuses such
as those found in programmable logic devices, but others are based on
SRAM equivalents. |
| aa |
| Field-Programmable Interconnect Chip
(FPIC) |
An alternative, proprietary name for a
field-programmable interconnect device
(FPID). |
| a |
| Field-Programmable Interconnect Device
(FPID) |
A device which is used to connect logic devices
together, and which can be dynamically reconfigured in the same way as
standard SRAM-based FPGAs. Because each FPID may have around 1,000 pins,
only a few such devices are typically required on a circuit
board. |
| a |
| FIFO (First-In
First-Out) |
A memory device in which data
is read out in the same order that it was written in. |
| a |
| Finite State
Machine (see
State Machine) |
| a |
| Firmware |
Refers to programs, or sequences of instructions,
that are hard-coded into non-volatile memory
devices. |
| a |
| First-In First
Out (FIFO) |
A memory device in which data is read out in the
same order that it was written
in. |