- The gate turn off thyristor is a three terminal device. The terminals names are anode, cathode and gate.
- It can be turned ON by applying a pulse of positive gate current and it can be turned OFF by applying a pulse of negative gate of proper amplitude.
- The GTO can resist higher voltage and current than the power transistor or MOSFET (metal oxide semiconductor FET). The V-I characteristic of GTO is shown in above figure.
- It is observed that the characteristics is in the forward direction is the same to that of conventionalSCR.
- In the reverse direction, GTO breaks down at a very low voltage. The reveres breakdown voltage is of the order of 20 to 30 V only.
- The latching current for large power GTO is in some amperes as compared to 100-500 mA for conventional thyristor same ratings.
- If the gate current is not able to turn ON the GTO it behaves like a high voltage low gaintransistor with significant anode current.
