Page 422 - Understanding Automotive Electronics

2735 | Glossary Page 409 Tuesday, March 10, 1998 1:33 PM

GLOSSARY G

Glossary

A/F: See Air/Fuel Ratio.
Accumulator: The basic work register of a computer.
Actuator: A device which performs an action in response to an electrical signal.
A/D (also ADC): Analog-to-digital converter; a device which is proportional
to the analog voltage level input.
Analog Circuits: Electronic circuits which amplify, reduce, or otherwise alter a
voltage signal which is a smooth or continuous copy of some physical quantity.
Assembly Language: An abbreviated computer language which humans can
use to program computers. Assembly language eventually is converted to
machine language so that a computer can understand it.
BDC: Bottom dead center; the extreme lowest position of the piston during its
stroke.
Bit: A binary digit; the smallest piece of data a computer can manipulate.
Block Diagram: A system diagram which shows all of the major parts and
their interconnections.
BSCO: Brake specific fuel consumption; the ratio of the rate at which fuel is
flowing into an engine to the brake horsepower being generated.
BSHC: Brake specific HC; the ratio of the rate at which hydrocarbons leave
the exhaust pipe to the brake horsepower.
BSNO : Brake specific NO ; the ratio of the rate at which oxides of nitrogen
x
x
leave the exhaust pipe to the brake horsepower.
Byte: 8 bits dealt with together.
CAFE: Corporate-Average-Fuel-Economy. The government mandated fuel
economy which is averaged over the production for a year for any given manu-
facturer.
Capacitor: An electronic device which stores charge.
Catalytic Converter: A device which enhances certain chemical reactions
which help to reduce the levels of undesirable exhaust gases.
Closed-Loop Fuel Control: A mode where input air/fuel ratio is controlled
by metering the fuel response to the rich-lean indications from an exhaust gas
oxygen sensor.
CO: Carbon monoxide; an undesirable chemical combustion product due to
imperfect combustion.
Combinational Logic: Logic circuits whose outputs depend only on the
present logic inputs
Combustion: The burning of the fuel-air mixture in the cylinder.

UNDERSTANDING AUTOMOTIVE ELECTRONICS 409