Unit 3 Lesson 6 Electronic Technology
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Unit 3 Lesson 6 Electronic Technology
Speaking in Code
What are electronics?
• Electronic devices like computers are not the
same as electrical devices like toasters. Both use
electrical energy. But electronic devices are able
to control the flow of electrons using integrated
circuits.
• An integrated circuit is a single, tiny chip of
specially treated silicon containing many circuit
parts. Integrated circuits carry out instructions, or
programs, by controlling current.
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Unit 3 Lesson 6 Electronic Technology
How can information be coded?
• A signal is a pattern that contains coded
information. For example, Morse code is a signal
that uses dashes and dots to represent letters of
the alphabet.
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Unit 3 Lesson 6 Electronic Technology
How can information be coded?
• Electronic devices also use coded signals. The two
kinds of signals they use are analog signals and
digital signals.
• Signals that change continuously in a given range
are called analog signals.
• A digital signal is a sequence of separate values.
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Unit 3 Lesson 6 Electronic Technology
How can information be coded?
• Information in a digital signal is represented using
a pattern called the binary code. Binary means
“two.”
• The digital binary code is made up of two digits: 1
and 0.
• In computers and other digital electronics, digital
signals are carried by a series of on-off electric
pulses. A 1 is encoded as a pulse. A 0 is encoded
as no pulse.
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Unit 3 Lesson 6 Electronic Technology
How can information be coded?
• An analog signal, like music, can be converted to
a digital signal and stored on a compact disc (CD).
• The flat, reflecting layer of a CD is called the land.
Data is recorded on the land in a spiral-shaped
series of bumps called pits.
• Inside a computer or CD player, a laser shines
light on a spinning CD. Pits are read as dark areas
because they reflect light differently than the land
does. The patterns of light and dark are
interpreted as a digital signal that can be
converted into your favorite song.
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Unit 3 Lesson 6 Electronic Technology
The Incredible Shrinking
Computer
How have computers changed?
• A computer is any electronic device that performs
tasks by following instructions given to it.
• Computers receive information, called input,
through keyboards, touchscreens, or other devices.
The input can be processed through a central
processor or stored in memory.
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Unit 3 Lesson 6 Electronic Technology
How have computers changed?
• Computers output information through monitors,
printers, or other devices. A microprocessor
controls and carries out the computer’s
instructions.
• A smartphone is a cell phone that is a mobile
computer with functions such as Internet access,
cameras, and built-in applications.
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