Triac

A triac (triode for alternating current) is a bidirectional thyristor that can conduct current in either direction when triggered. It's widely used for AC power control applications.

Terminals

t1 - Terminal 1 (bidirectional)
gate - Control terminal
t2 - Terminal 2 (bidirectional)

Parameters

Parameter	Type	Default	Description
`name`	String	required	Component identifier
`Vbo`	Real	30	Breakover voltage (V)
`Cj0`	Real	1e-11	Zero-bias junction capacitance (F)
`Is`	Real	1e-10	Saturation current (A)
`N`	Real	2	Emission coefficient
`Ri`	Real	10	Intrinsic region resistance (Ω)
`Rg`	Real	5	Gate resistance (Ω)
`Temp`	Real	26.85	Temperature (°C)

Example

using CircuitSim

circ = Circuit()

triac = Triac("triac1", Vbo=30)
vt = DCVoltageSource("vt", voltage=20.0)
vg = DCVoltageSource("vg", voltage=0.15)
rg = Resistor("rg", resistance=1000.0)
gnd = Ground("gnd")

add_component!(circ, triac)
add_component!(circ, vt)
add_component!(circ, vg)
add_component!(circ, rg)
add_component!(circ, gnd)

@connect circ vt.nplus triac.t1
@connect circ triac.t2 gnd.n
@connect circ vg.nplus rg.n1
@connect circ rg.n2 triac.gate
@connect circ vg.nminus gnd.n
@connect circ vt.nminus gnd.n

println(netlist_qucs(circ))

# Qucs netlist generated by CircuitSim.jl
Triac:triac1 _net3 _net1 gnd Vbo="30"
Vdc:vt _net3 gnd U="20.0"
Vdc:vg _net2 gnd U="0.15"
R:rg _net2 _net1 R="1000.0"

The triac conducts when triggered by the gate signal, allowing bidirectional current flow. Unlike a thyristor, it can be triggered in either polarity.