Vdrm(V)

(Repetitive forward peak off-stage voltage) Maximum allowable instantaneous value of repetitive off-state voltage that may be applied across a bidirectional thyristor (forward or reverse direction) or SCR (forward direction only)

It(rms)(A)

(On-state Current) Anode cathode principal current that may be allowed under stated conditions, usually the fullcycle RMS current

Itsm(A)

(Non-Repetitive Peak On-State Current) the maximum permissible peak value of a single half sine-wave 50Hz current pulse.

Idrm(uA)

(Repetitive Peak Off-state Current) Maximum leakage current that may occur under the conditions of VDRM

VTM(V)

(On-state Voltage) Principal voltage when the thyristor is in the on state

Ih(mA)

(Holding Current) Minimum principal current required to maintain the thyristor in the on-state

Igt(mA)max

(Gate trigger current) Minimum gate current required to switch a thyristor from the off state to the on state

(dV/dt)cr

(Critical rate of rise of off-state voltage) Maximum value of the rate-of-rise of principal voltage which will cause switching from the off state to the on state