VS-ST173C12CFP1

Thyristors - SCRs - VS-ST173C12CFP1 Application Field and Working Principle

A thyristor is a semiconductor device which includes a Gate, Cathode, Anode and body. It is known as a four layer PNPN diode, it serves as a switch for controlling electric current in power circuits, Thyristors can control large amounts of energy, store it to be used later, act as switches, rectifiers and phase control devices along with other thyristor based applications.

The VS-ST173C12CFP1 is a three phase Thyristor which stands out due to its robust construction and reliable quality. It is used in voltage supplied applications such as AC motors, lamps, heating element, pumps and power controlled systems. This Thyristor is used in applications where two thyristors are required to fire simultaneously as it has two built in anodes. It is popular due to its low switching losses and integrated structure.

Working Principle

The Thyristor acts like a three-layer diode, consisting of a P-type layer sandwiched in between N-type layers. When the P-layer is triggered the current gets the ability to flow through it. When the P layer is reverse biased, it no longer conducts. When the P layer is forward biased, the voltage level is reduced, hence allowing current flow through the junction. This action is referred to as turn-on or conduction.

Additionally, VS-ST173C12CFP1 Thyristors have an internal Gate circuit. If a gate current preferably higher than the holding current is applied, the gate current induces a current in the control electrode causing an electric field to be generated between the anode and cathode, leading to conduction. Thus, the gate current gates the thyristor in conducting state. At the same time, sufficient negative voltage applied at the Gate terminal can drive the Thyristor into blocking mode.

An important physical characteristic of a Thyristor is that it can conduct in both directions (positive as well as negative). In other words, the anode and cathode can interchange their roles. The mode of operation of this device can be reversed if the polarity at its terminals is changed.

Features

The VS-ST173C12CFP1 has a wide operating temperature range, has zero temperature coefficient and its forward voltage drop is low. The maximum operating temperature of this device is 150°C due to its better thermal management. Additional features such as minimised losses and low inductance of these thyristors make them a suitable choice for applications such as motor speed control, AC switches, audio circuits and voltage selectors.

VS-ST173C12CFP1 Thyristors also offer great advantages in terms of its on-state resistance, surge capability and reverse recovery times. The surge capability of this thyristor is high, allowing it to withstand spikes and inrush currents, while its reverse recovery time is low, allowing it to switch different currents quickly.

Conclusion

The VS-ST173C12CFP1 offers good performance in terms of tolerance, reliability, and switching speeds. It is an ideal choice for applications where two thyristors are required to be fired simultaneously. It is suitable for three phase applications and due to its low switching losses and integrated structure makes it popular in the market.