onsemi 2N6509G High-Current TRIAC: Datasheet, Pinout, and Application Circuits
The onsemi 2N6509G is a robust, standard-offer, high-current TRIAC designed for a wide range of AC switching and control applications. This component is engineered to handle significant power levels, making it a suitable choice for industrial controls, motor drivers, heating regulation, and solid-state relays. Its ability to switch AC waveforms efficiently in both directions provides a simple and cost-effective solution for controlling power delivered to a load.
Datasheet Overview and Key Specifications
The datasheet for the 2N6509G outlines its electrical characteristics and absolute maximum ratings, which are critical for reliable circuit design.
High Current Capability: It features a repetitive peak on-state current (Iₜₛₘ) of 25 A and a non-repetitive peak on-state surge current (Iₜₛₘ) of 250 A, highlighting its ability to handle high inrush currents, commonly encountered when driving inductive loads like motors.
Blocking Voltage: The device offers a repetitive peak off-state voltage (VDRM) of up to 600 V, making it suitable for use in 110V and 240V AC mains applications.
Gate Triggering: The gate trigger current (Igt) is a low 35 mA, which allows it to be driven directly from microcontrollers or logic circuits when using an appropriate buffer or driver stage.
Package: It is offered in the robust TO-220AB package, which provides excellent thermal performance and facilitates easy mounting to a heatsink for dissipating the generated power loss.
Pinout Configuration
The pinout for the TO-220AB package is standard for such devices. When holding the component with the flat face toward you and the pins pointing downward:
Pin 1 (Left): Main Terminal 2 (MT2). This is typically connected to the load or the AC supply.
Pin 2 (Middle): Main Terminal 1 (MT1). This is the reference terminal for the gate trigger pulse and is usually connected to the other side of the AC supply.
Pin 3 (Right): Gate (G). The control terminal where a trigger pulse relative to MT1 is applied to switch the TRIAC into conduction.
Application Circuits
Two fundamental application circuits demonstrate the use of the 2N6509G.
1. Basic AC Switch Circuit:
This is the simplest form of TRIAC control. The TRIAC is connected in series with the load (e.g., a heater or lamp) across the AC mains. A switch is connected between the Gate and MT2. When the switch is closed, current flows through the gate, triggering the TRIAC to conduct for the remainder of that AC half-cycle. This circuit provides simple on/off control but offers no phase-angle control.
2. Phase-Angle Control Circuit (Dimmer):
For applications like light dimming or motor speed control, a phase-angle control circuit is used. This circuit typically consists of a diac (e.g., DB3) and a variable resistor-capacitor (RC) network. The capacitor charges through the variable resistor. When the voltage across the capacitor exceeds the breakover voltage of the diac, it fires and delivers a sharp pulse to the gate of the 2N6509G, triggering it. By adjusting the variable resistor, the timing of the trigger pulse within the AC cycle is varied, thus controlling the average power delivered to the load. A snubber circuit (a resistor and capacitor in series) is often placed across the TRIAC (MT1 to MT2) to suppress voltage spikes caused by inductive loads.
ICGOODFIND Summary
The onsemi 2N6509G is a highly reliable and powerful TRIAC optimized for demanding AC switching tasks. Its high current and voltage ratings, combined with a standard TO-220 package, make it an excellent choice for designers creating industrial equipment, domestic appliances, and lighting control systems. Proper heatsinking and attention to snubber circuits for inductive loads are essential for maximizing performance and longevity.
Keywords: TRIAC, AC Switching, Phase-Angle Control, High-Current, Solid-State Relay
