Electronic symbol

Wire crossover symbols for circuit diagrams. The CAD symbol for insulated crossing wires is the same as the older, non-CAD symbol for non-insulated crossing wires. To avoid confusion, the wire "jump" (semi-circle) symbol for insulated wires in non-CAD schematics is recommended (as opposed to using the CAD-style symbol for no connection), so as to avoid confusion with the original, older style symbol, which means the exact opposite. The newer, recommended style for 4-way wire connections in both CAD and non-CAD schematics is to stagger the joining wires into T-junctions. The large dot signifies an electrical connection.

• 
  Trace connection
  (IEC-style)
• 
  Trace junction
  (IEC-style)
• 
  Trace crossing (unconnected)
• 
  Trace crossing
  (hand drawn schematics)

The shorthand for ground is GND. Optionally, the triangle in the middle symbol may be filled in.

• 
  General ground
  (IEC-style)
• 
  Signal/low-noise ground (the asterisk is not part of the symbol)
• 
  Chassis ground
  (IEC-style)

• 
  Battery, single-cell
• 
  Battery, multi-cell
• 
  Solar cell (photovoltaic cell)

• 
  DC voltage source
• 
  Controlled DC voltage source
• 
  Current source
• 
  Controlled current source
• 
  AC voltage source

It is very common for potentiometer and rheostat symbols to be used for many types of variable resistors, including trimmers.

• 
  ANSI-style: (a) Resistor, (b) Rheostat,
  (c) Potentiometer / Trimmer
• 
  IEC-style: (a) Resistor, (b) Rheostat,
  (c) Potentiometer / Trimmer

• 
  Photoresistor (ANSI)
• 
  Thermistor (ANSI).[5]
  Use -t for NTC symbol.
  Use +t for PTC symbol.
• 
  Varistor (ANSI)

• 
  General capacitor
  (IEC-style)
• 
  Polarized capacitor
  (American-style)
• 
  Variable capacitor
• 
  Ganged (co-moving) variable capacitors
  (IEC-style)
• 
  Trimmer variable capacitor

Optionally, the triangle in these symbols may be filled in. Note: The words anode and cathode typically aren't part of the diode symbols.

• 
  Diode (rectifier)
• 
  Schottky diode
• 
  Zener diode
• 
  Transient-voltage-suppression diode (TVS)
• 
  Light-emitting diode (LED)
• 
  Photodiode
• 
  Tunnel diode
• 
  Varicap
• 
  Shockley diode
• 
  Silicon-controlled rectifier (SCR)
• 
  Diac (may be a varistor in older schematics)
• 
  Constant-current diode
• 
  Opto-isolator: LED (left), photo transistor (right)

There are many ways to draw a single-phase bridge rectifier symbol. Some show the internal diode circuit, some don't.

• 
  Bridge rectifier
• 
  Bridge rectifier
• 
  Bridge rectifier
• 
  Bridge rectifier
• 
  Three-phase bridge rectifier

• 
  Air-core inductor
  (IEC-style)
• 
  Magnetic-core inductor
  (IEEE-style)
• 
  Tapped inductor
  (IEC-style)
• 
  Ferrite bead
  (IEEE-style)

• 
  Transformer
• 
  Transformer with center tap on secondary winding (right side)
• 
  Transformer with two secondary windings (right side)
• 
  Current transformer
• 
  Zero-sequence current transformer (ZSCT) (also known as a window-type current transformer)
• 
  Bushing-type current transformer
• 
  Voltage transformer

Optionally, transistor symbols may include a circle.[6] Note: The pin letters B/C/E and G/D/S aren't part of the transistor symbols.

• 
  NPN bipolar junction transistor (BJT)
• 
  PNP bipolar junction transistor (BJT)
• 
  NPN Darlington transistor
• 
  PNP Darlington transistor

• 
  N-channel junction gate field-effect transistor (JFET)
• 
  P-channel junction gate field-effect transistor (JFET)
• 
  Metal–oxide–semiconductor field-effect transistor (MOSFET)
• 
  Enhancement mode, N-channel MOSFET
• 
  Enhancement mode, P-channel MOSFET

• 
  Vacuum tube diode
• 
  Vacuum tube triode
• 
  Vacuum tube tetrode
  (pin letters are not part of the symbol)
• 
  Vacuum tube pentode

• 
  Pushbutton, normally open, push-to-make (horizontal line on top)
• 
  Pushbutton, normally open, push-to-make (IEEE-style)
• 
  Pushbutton, normally closed, push-to-break (IEEE-style)
• 
  Pushbutton, normally closed, two circuits (IEEE-style)

• 
  Switch, 1P1T, SPST (single-pole single-throw)
• 
  Switch, 1P2T, SPDT (single-pole double-throw)
• 
  Switch, 2P1T, DPST (double-pole single-throw)
• 
  Switch, 2P2T, DPDT (double-pole double-throw)

• 
  Slide switch, 1P3T,
  break-before-make, nonshorting style
• 
  Slide switch, 1P4T,
  break-before-make, nonshorting style
• 
  Slide switch, 1P4T,
  make-before-break, shorting style

• 
  Rotary switch, 1P3T,
  break-before-make, nonshorting style
• 
  Rotary switch, 1P4T,
  break-before-make, nonshorting style
• 
  Rotary switch, 1P4T,
  make-before-break, shorting style

• 
  Reed switch, normally open

Note: The pin letters aren't part of the symbols.

• 
  SPST, SPDT, DPST, DPDT relays
  (American-style)
• 
  SPDT relay
  (IEC-style)

LED is located in diode section.

• 
  Neon lamp
• 
  Indicating lamp
  (IEEE-style)
• 
  Incandescent lamp
• 
  Incandescent light bulb (as an indicator)
• 
  Light bulb

• 
  IEC fuse (b), equivalent symbols (a, c) (IEEE Std 315-1975)
• 
  Molded-case circuit breaker (MCCB)
• 
  Fuse: IEC (top) and American (lower two)

• 
  Loudspeaker
  (IEEE-style)
• 
  Buzzer
  (IEC-style)
• 
  Microphone
  (IEEE-style)
• 
  Microphone
  (IEC-style)

• 
  General antenna
  (IEC-style)
• 
  Dipole antenna
  (IEC-style)
• 
  Loop antenna
  (IEC-style)
• 
  Loop antenna
  (IEEE-style)

• 
  Cable, Shielded 1 conductor
• 
  Cable, 2 conductor
• 
  Cable, Shielded 2 conductor with shield connected to ground
• 
  Cable, 5 conductor
• 
  Cable, Shielded 5 conductor

• 
  TRS phone jacks

For the symbols below: A and B are inputs, Q is output. Note: These letters are not part of the symbols.

There are variations of these logic gate symbols. Depending on the IC, the two-input gates below may have: 1) two or more inputs; 2) infrequently some have a second inverted Q output too.

• 
  Buffer
• 
  Inverter (NOT)
• 
  AND
• 
  NAND
• 
  OR
• 
  NOR
• 
  XOR
• 
  XNOR

The above logic symbols may have additional I/O variations too: 1) schmitt trigger inputs, 2) tri-state outputs, 3) open-collector or open-drain outputs (not shown).

• 
  Buffer gate with schmitt trigger input
• 
  Buffer gate with tri-state output control.
  (B is the tri-state control)

For the symbols below: Q is output, Q is inverted output, E is enable input, internal triangle shape is clock input, S is Set, R is Reset (some datasheets use clear (CLR) instead of reset along the bottom).

There are variations of these flip-flop symbols. Depending on the IC, a flip-flop may have: 1) one or both outputs (Q only, Q only, both Q & Q); 2) one or both forced inputs along top & bottom (R only, S only, both R & S); 3) some inputs may be inverted.

• 
  Simple SR flip-flop (inverted S & R inputs)
• 
  Gated SR flip-flop
• 
  Gated D flip-flop (Transparent Latch)
• 
  Clocked D flip-flop
  (Set & Reset inputs)
• 
  Clocked JK flip-flop
• 
  Clocked T flip-flop

Note: The outside text isn't part of these symbols.

• 
  Operational amplifier (opamp)
• 
  Comparator

• 
  Crystal oscillator
  (IEEE-style)
• 
  Ceramic resonator
  (3 pins)

• 
  Hall-effect sensor
• 
  Gas-discharge tubes (GDT) for ESD discharge
• 
  Spark gap
  for ESD discharge

All of the following are obsolete capacitor symbols.

• 
  Obsolete capacitor
  (very old style)
• 
  Obsolete capacitor
• 
  Obsolete capacitor
• 
  Obsolete capacitor
• 
  Obsolete capacitor