Thyristors - TRIACs

Image	Part Number	Description / PDF	Quantity	Rfq
	Q6008VH3 Wickmann / Littelfuse	TRIAC ALTERNISTOR 600V 8A TO251	0
	L601E375 Wickmann / Littelfuse	TRIAC SENS GATE 600V 1A TO92	0
	Q6004F31 Wickmann / Littelfuse	TRIAC SENS GATE 600V 4A TO202	0
	L2004V5 Wickmann / Littelfuse	TRIAC SENS GATE 200V 4A TO251	0
	QK012LH2 Wickmann / Littelfuse	TRIAC ALTERNISTOR 1KV 12A TO220	0
	L4004V3 Wickmann / Littelfuse	TRIAC SENS GATE 400V 4A TO251	0
	Q4004F441 Wickmann / Littelfuse	TRIAC 400V 4A TO202	0
	L6004V8 Wickmann / Littelfuse	TRIAC SENS GATE 600V 4A TO251	0
	Q6025LH5 Wickmann / Littelfuse	TRIAC ALTERNISTOR 600V 25A TO220	0
	Q4010F51 Wickmann / Littelfuse	TRIAC 400V 10A TO202	0
	Q201E3 Wickmann / Littelfuse	TRIAC SENS GATE 200V 1A TO92	0
	Q2004F42 Wickmann / Littelfuse	TRIAC 200V 4A TO202	0
	Q2004L3 Wickmann / Littelfuse	TRIAC SENS GATE 200V 4A TO220	0
	Q8008LH4 Wickmann / Littelfuse	TRIAC ALTERNISTOR 800V 8A TO220	0
	Q2008L4 Wickmann / Littelfuse	TRIAC 200V 8A TO220	0
	L6006L6 Wickmann / Littelfuse	TRIAC SENS GATE 600V 6A TO220	0
	L4006V5 Wickmann / Littelfuse	TRIAC SENS GATE 400V 6A TO251	0
	L2004L3 Wickmann / Littelfuse	TRIAC SENS GATE 200V 4A TO220	0
	Q8008VH3 Wickmann / Littelfuse	TRIAC ALTERNISTOR 800V 8A TO251	0
	Q2025R5 Wickmann / Littelfuse	TRIAC 200V 25A TO220	0

Thyristors - TRIACs

1. Overview

TRIAC (Triode for Alternating Current) is a three-terminal semiconductor device belonging to the thyristor family. It enables bidirectional current flow control in AC circuits through a single gate terminal. As a key component in power electronics, TRIACs are widely used for phase control, switching, and regulation of AC loads. Their ability to conduct current in both directions makes them ideal for applications requiring full-wave control, such as dimmers and motor speed regulators.

2. Main Types and Functional Classification

Type	Functional Characteristics	Application Examples
Standard TRIAC	General-purpose with moderate gate sensitivity	Light dimmers, heater controls
Sensitive Gate TRIAC	Low gate trigger current ( 5mA)	Microcontroller-driven circuits
Logic Level TRIAC	Compatible with 3.3V/5V logic signals	Smart home automation systems
High dv/dt TRIAC	Enhanced immunity to voltage spikes	Industrial motor drives

3. Structure and Composition

TRIACs feature a four-layer (PNPN) silicon structure with three electrodes: Main Terminal 1 (MT1), Main Terminal 2 (MT2), and Gate (G). The symmetrical design allows bidirectional conduction. Modern TRIACs incorporate:

Dielectric passivation layers for voltage stability
Aluminum gate metallization
Epitaxial silicon wafers with precise doping profiles
Plastic encapsulation (TO-220/TO-92 packages)

4. Key Technical Parameters

Parameter	Description	Typical Range
Breakover Voltage (VBO)	Minimum voltage to initiate conduction	200-1200V
Gate Trigger Current (IGT)	Required gate current for turn-on	5-50mA
Holding Current (IH)	Minimum current to maintain conduction	5-50mA
RMS On-State Current (IT(RMS))	Continuous load current capacity	0.5-50A
dv/dt Rating	Voltage change immunity	10-50V/ s

5. Application Fields

Consumer Electronics: Smart lighting systems, washing machine water level controls
Industrial Automation: AC motor speed controllers, solid-state relays
Power Systems: Voltage regulators, reactive power compensators
Automotive: Electric vehicle charging circuits, HVAC controls
Renewable Energy: Solar inverter AC switching circuits

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Parameters
STMicroelectronics	BT136-600E	600V, 4A, 10mA IGT
ON Semiconductor	Q6015LH	600V, 15A, 15mA IGT
Infineon Technologies	BTA16-600B	600V, 16A, 50mA IGT
Microsemi	MAC97A8	600V, 8A, 5mA IGT

7. Selection Guidelines

Verify VBO exceeds maximum circuit voltage by 20%
IT(RMS) should be 1.5 load current
Match IGT with driver circuit capability
Consider heatsinking requirements
Select dv/dt rating based on load inductance
Use zero-crossing detection for EMI-sensitive applications

8. Industry Trends

Key development trends include:

Integration with SiC/GaN for higher efficiency
Smart packaging with built-in temperature sensors
Miniaturization for space-constrained applications
Improved immunity to electromagnetic interference
AI-driven predictive maintenance in industrial systems

Market growth is driven by smart grid implementations and EV charging infrastructure expansion, with a projected CAGR of 6.8% through 2030.