COMPONENT SYMBOL PICTURE/
DRAWINGDESCRIPTION
Wire To conduct or pass current from one part of a circuit to another.
Connected Wires
help to transmit current to other paths
SPST Toggle Switch
Disconnects current when open
SPDT Toggle Switch
Selects between two connections
Pushbutton Switch (N.O)
Momentary switch - normally open
Pushbutton Switch (N.C)
Momentary switch - normally closed
DIP SwitchDIP switch is used for onboard configuration
SPST RelayRelay open / close connection by an
electromagnet
SPDT RelayRelay open / close connection by an
electromagnet
JumperClose connection by jumper insertion on
pins.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Solder BridgeSolder to close
connection
Earth Ground
Used for zero potential reference and electrical shock
protection.
Chassis GroundConnected to the
chassis of the circuit
Fuse
A safety device, which will 'blow' or melt if the current flowing through itexceeds a
specified value.
Resistor (IEEE)Resistor reduces the
current flow.
Resistor (IEC)Resistor reduces the
current flow.
Potentiometer (IEEE)
Adjustable resistor - has 3 terminals
Potentiometer (IEC)
Adjustable resistor - has 3 terminals
Variable Resistor / Rheostat (IEEE)
Adjustable resistor - has 2 terminals.
Variable Resistor / Rheostat (IEC)
Adjustable resistor - has 2 terminals.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Trimmer Resistor Preset resistor
Thermistor
Thermal resistor - change resistance when temperature
changes
Photo resistor / Light dependent
resistor (LDR)
Photo-resistor - change resistance with light intensity
change
CapacitorCapacitor is used to
store electric charge. It acts as short circuit
with AC and open circuit with DC.
Capacitor
Capacitor is used to store electric charge. It acts as short circuit
with AC and open circuit with DC.
Polarized Capacitor
Electrolytic capacitor
Polarized Capacitor
Electrolytic capacitor
Variable CapacitorAdjustable
capacitance
InductorCoil / solenoid that
generates magnetic field
Iron Core Inductor Includes iron
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Variable Inductor A coil whose effective inductancecan be
changed.
Voltage SourceGenerates constant
voltage
Current SourceGenerates constant
current.
AC Voltage Source AC voltage source
Generator
Electrical voltage is generated by
mechanical rotation of the generator
CellGenerates constant
voltage
BatteryGenerates constant
voltage
Controlled Voltage Source
Generates voltage as a function of voltage or current of other
circuit element.
Controlled Current Source
Generates current as a function of voltage or current of other
circuit element.
VoltmeterMeasures voltage. Has very high resistance. Connected in parallel.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Ammeter
Measures electric current. Has near zero resistance. Connected
serially.
Ohmmeter Measures resistance
WattmeterMeasures electric
power
Lamp / light bulbGenerates light when current flows through
Lamp / light bulbGenerates light when current flows through
Lamp / light bulbGenerates light when current flows through
Diode
Diode allows current flow in one direction only - left (anode) to
right (cathode).
Zener Diode
Allows current flow in one direction, but also
can flow in the reverse direction
when above breakdown voltage
Schottky DiodeSchottky diode is a
diode with low voltage drop
Varactor / Varicap Diode
Variable capacitance diode
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Tunnel Diode
used for amplifying, switching, and
computer information storage and as an
oscillator
Light Emitting Diode (LED)
LED emits light when current flows through
PhotodiodePhotodiode allows current flow when exposed to light
NPN Bipolar Transistor
Allows current flow when high potential at
base (middle)
PNP Bipolar Transistor
Allows current flow when low potential at
base (middle)
Darlington Transistor
Made from 2 bipolar transistors. Has total gain of the product of
each gain.
JFET-N TransistorN-channel field effect
transistor
JFET-P TransistorP-channel field effect
transistor
NMOS TransistorN-channel MOSFET
transistor
PMOS TransistorP-channel MOSFET
transistor
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Motor Electric motor
TransformerChange AC voltage from high to low or
low to high.
Electric bell Rings when activated
BuzzerProduce buzzing
sound
Fuse
The fuse disconnects when current above threshold. Used to protect circuit from
high currents.
Fuse
The fuse disconnects when current above threshold. Used to protect circuit from
high currents.
Step Up Transformer
The no. of turns in secondary winding is
more than that of primary winding.
Step Down Transformer
The no. of turns in secondary winding is
less than that of primary winding.
Crystal Oscillator
Used to generate clock signal of very precise frequency.
Optocoupler / Opto-isolator
Optocoupler isolates connection to other
board
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
LoudspeakerConverts electrical
signal to sound waves
MicrophoneConverts sound waves
to electrical signal
Operational Amplifier
Amplify input signal
Schmitt TriggerOperates with
hysteresis to reduce noise.
Analog-to-digital converter (ADC)
Converts analog signal to digital
numbers
Digital-to-Analog converter (DAC)
Converts digital numbers to analog
signal
Crystal OscillatorUsed to generate precise frequency
clock signal
Antenna / aerial
Transmits & receives radio waves
Antenna / aerial
Transmits & receives radio waves
Dipole AntennaTwo wires simple
antenna
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
NOT Gate (Inverter)
Outputs 1 when input is 0
AND GateOutputs 1 when both
inputs are 1.
NAND GateOutputs 0 when both inputs are 1. (NOT +
AND)
OR GateOutputs 1 when any
input is 1.
NOR GateOutputs 0 when any
input is 1. (NOT + OR)
XOR GateOutputs 1 when
inputs are different. (Exclusive OR)
D Flip-Flop Stores one bit of data
Multiplexer / Mux 2 to 1
Connects the output to selected input line.
Multiplexer / Mux 4 to 1
Connects the output to selected input line.
Demultiplexer / Demux 1 to 4
Connects selected output to the input
line.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Electric generatorElectrical voltage is
generated by mechanical rotation of
the generator
Unjoined wiresThis can only be shown by
bridging them or by drawing them without blobs. But bridging is
commonly practised as there will not arise any
confusion.
DC SupplyUsed as a DC power supply, that is, the
current will always flow in one direction.
AC SupplyUsed as AC power supply, that is, the current will keep
alternating directions.
Transformer Used as an ac power supply.
Earth/GroundUsed in electronic
circuits to represent the 0 volts of the
power supply
RheostatUsed to control the
current flow with two contacts
Potentiometerused to control the
voltage flow and has three contacts
Presetlow cost variable
resistors that are used to control the charge flow with the help of a
screw driver
Zener DiodeAfter a breakdown voltage, the device
allows current to flow in the reverse direction
as well.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Photo DiodeWorks as a photo-
detector and converts light into its
corresponding voltage or current.
Phototransistorsimilar to that of a
bipolar transistor with a difference that it
converts light into its corresponding current..
Field Effect Transistor
The device has an electric field that
controls the conductivity of a
channel of one type charge carrier in a
semiconductor substance.
N-Channel Junction FET
Is the simplest type of FET with applications in Switching and voltage
variable resistor.
P-Channel Junction FET
P-channel JFET is similar in construction
to N-channel JFET except that P-type
semiconductor base is sandwiched between two N-type junctions.
Metal Oxide Semiconductor
FET
A three terminal device and is controlled by a
gate bias
EX-NOR Gate
Short form for Exclusive NOT OR. If
both the inputs are the same, the output will
be HIGH.
NOT Gate
Also known as the inverter Gate. There is only one input for this
gate
GalvanometerUsed to measure very small currents in the
order of 1 milli ampere or less.
OscilloscopeUsed to measure the
voltage and time period of signals along
with their shape display.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Light Dependent Resistor
Used to convert light into its corresponding
resistance.
Thermistor Senses the heat content and converts it
into resistance.
Push SwitchThis is an ordinary switch that passes current only upon
pressing.
Push to Break Switch
The push to break switch is usually kept
in the ON state (closed). It turns to OFF state (open) only when the switch is pressed.
Single Pole Single Throw switch
Also known as the ON/OFF switch. This
switch allows the flow of current only when it
is kept ON.
Single Pole Double Throw Switch
Also known as the 2-way switch. It can be
also called as an ON/OFF/ON switch as it has an OFF position in
the center
Double Pole Single Throw Switch
. This is used to isolate between the live and neutral connections in
the main electrical line.
Double Pole Double Throw
Switch
The switch uses a central OFF position
and is applied as reversing switch for
motors.
RelayThis device can easily switch a 230 Volt AC
mains circuit.
EarphoneDoes the reverse
process of microphone
and converts electrical
energy into sound.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Piezo-transducerIt is a transducer that
converts electrical energy into sound.
AmplifierUsed to amplify a
signal. It is mainly used to represent a whole
circuit rather than just one component.
AerialThis device is used to
transmit/receive signals
Lighting LampThis is used to provide
light for the output.
Indicator LampUsed to convert
electrical energy into light. The best example is the warning light on
a car dashboard.
HeaterThis transducer is used
to change electrical energy into heat.
Bell
Used to produce a sound as the output, according to the electrical energy produced as the input.
BuzzerIt is used to produce an
output sound corresponding to the
electrical energy in the input.
Enhanced MOSFET
Voltage is applied to the gate, so as to
develop a channel of charge carriers so that a current results when
a voltage is applied across the drain-source
terminals
Depletion MOSFETIn the depletion-mode construction a channel
is physically constructed and a
current between drain and source is due to
voltage applied across the drain-source
terminals.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Capacitor-Polarized
Capacitor can be used in a timer circuit by adding a resistor.
Equipotentialitya symbol to identify parts
that have the same voltage
Chassis Connected to the chassis of the circuit.
AttenuatorIt is a device used to
lower the power of a
signal.
AccumulatorAccumulators are
designed to increase or
relieve pressure in the
system.
AntennaA antenna is a radio antenna that can be
made of a simple wire, with a center-fed driven
element.
Loop AntennaA loop antenna is a radio antenna consisting of a loop (or loops) of wire, tubing, or other electrical conductor with its ends connected to a balanced transmission line.
Circuit BreakerA circuit breaker is an
automatically operated electrical switch designed
to protect an electrical circuit from damage
caused by overload or short circuit.
Explosive SquibExplosive squib is often
used on stage and film to
trigger various special
effects.
OscillatorProduces a repetitive
electronic signal, often a sine wave or a square
wave.
COMPONENT SYMBOL PICTURE/ DRAWING
DESCRIPTION
Memristorused in signal processing,
logic/computation, non-volatile memory
etc.
Electrolytic Capacitor
Almost all electrolytic capacitors are
polarized and hence used in DC circuits
Feed through Capacitor
They provide low impedance path to
ground for high frequency signals
Ferrite Core Inductors
These are mostly used to suppress the interference of
electromagnetic waves.
Thyristor
It consists of four layers of alternating P and N materials. They
act as bistable switches and are used in circuits where high voltages and currents
are involved.
Laser DiodeThe laser diode is
similar to light emitting diode.
Photo DarlingtonPhoto Darlington Transistor is similar to phototransistor with very high gain and sensitivity
BufferIt is an audio signaling
device. Generally used in alarms, timers and for confirmation
messages.
Tri-State BufferSimilar to a normal buffer but with a
control signal
Flip FlopFlip flop is the also a memory element but this is a synchronous
device
ELECTRICAL AND ELECTRONICS
SYMBOLS
PLATE NO. 1
SUBMITTED BY: NICKKY AUREPHIL B. GERONIMO
SUBMITTED TO: ENGR. TUBAN