Parameters And Ratings
General Note
Unless explicitly mentioned in conditions, all data given in the data sheets are valid over the entire operating temperature of -40°C ---Tjm.

Non-repetitive peak off-state and reverse voltage V_DRM and V_RRM
Maximum allowable peak value of non-repetitive transient off-state and reverse voltages.

Repetitive peak off-state and reverse voltage V_DRM and V_RRM
Maximum allowable peak value of repetitive transient off-state and reverse voltages.

Mean on-state current I_TAV ( I_FAV )
Absolute maximum value of continuous on-state (forward) current for the current waveforms, temperatures and cooling conditions stated, with no margins for overload. At this current the maximum allowable junction temperature will be reached. In practical applications, to allow for current or voltage overloads, for degradation of cooling conditions, and for increases in the ambient temperature by, for example, local heating due to adjacent components, it is recommended that only 80 % of maximum mean on-state (forward) current as given is utilized.

RMS on-state current I_TRMS
Absolute maximum value of continuous rms current for the chosen current conduction angle, waveform, and cooling conditions.

Allowable overload currents
The overload currents which are permissible for short-term overloads, for intermittent duty or at frequencies below 40 Hz may be calculated by means of the transient thermal impedance or the thermal impedance under pulse conditions , so that the virtual junction temperature at no instant exceeds the specified maximum value.

Surge on-state ( forward ) current I_TSM ( I_FSM )
Maximum peak value of a single half sine wave current surge of 10 ms duration. After occasional current surges up to this limiting value the thyristor (diode) will withstand the peak reverse voltages stated.

I²t value
The I2t value for the thyristor or diode is given to assist in the selection of suitable fuses to protect against damage due to short circuits. The I2t value of the fuse for the prospective short circuit current and for the input voltage used must be less than the value for the thyristoror diode for t = 10 ms. Since the I2t value of the fast operating fuses normally used for the protection falls more rapidly with increasing temperature than the I2t value for the thyristor or diode, it is generally sufficient to compare the I2tvalue of the thyristor or diode at 25°C with the I2t value of the (unloaded) fuse.

Gate trigger voltage V_GT and trigger current I_GT
These are the lowest values of gate voltage and current with a 100 us pulse and anode voltage of 12V which will ensure firing.