Thyristors - TRIACs

The Q2006NH4RP is a TRIAC (Triode for Alternating Current) that belongs to the family of Thyristors. It is a six-layer, low power switching device, available in a TO-220AB package. It is designed for AC load control applications such as lamp and fan speed control, light dimmers, heater control, and motor control.

TRIACs are the electronic equivalents of a mechanical switch. The Q2006NH4RP is constructed in such a way that its functioning is completely analogous to a mechanical switch. When connected to an AC voltage source, the TRIAC is non-conducting. If a firing signal is applied to its gate terminal, the TRIAC switches on and the load is enabled.

Working Principle

The Q2006NH4RP is designed for two main purposes: switching AC power and providing exact control of the conduction angle. When considering how a TRIAC works, it is important to remember that it can conduct current in both directions. This is because a TRIAC is an asymmetrical device. When a small trigger current is applied to the gate of a TRIAC, the current is conducted through the whole device.

In an AC circuit, the TRIAC conducts until the voltage returned to zero. When the voltage decreases, the current is no longer conducted through the TRIAC and it is considered off. A TRIAC is triggered by an edge of the waveform (positive or negative) that is greater than the triggering voltage. This is known as the “firing” voltage.

Once a TRIAC is triggered, it will conduct current until the reverse voltage drops below the off voltage. This voltage is usually one volt.

The manner of triggering and firing is where the TRIAC differs from a mechanical switch. A mechanical switch is only triggered once at the start of the circuit, whereas a TRIAC is triggered and fired over and over as the circuit repeats. This allows for accurate control of the conduction angle of the TRIAC.

Applications

The Q2006NH4RP can be used in a variety of applications. These include motor control, lighting control, heating control, and fan speed control.

The Q2006NH4RP is ideal for motor control applications because it is capable of providing variable speed control. By adjusting the conduction angle, the power supplied to the motor can be varied, allowing for precise control of its speed.

Additionally, theQ2006NH4RP is relatively low power, making it a great choice for applications such as light dimmers, heaters, and fan speed control. All of these applications need precise control of power consumption, and the TRIAC provides just that.

Conclusion

The Q2006NH4RP is an ideal choice for AC load control applications. Its wide operating range, low saturation voltage, and precise control of the conduction angle make it a great choice for motor control and other variable speed applications.