Editing TRIAC (section)

=== Static dv/dt ===
A high <math>\operatorname{d}v\over\operatorname{d} t</math> between MT2 and MT1 may turn on the TRIAC when it is off. Typical values of critical static d''v''/d''t'' are in the terms of volts per microsecond.

The turn-on is due to a parasitic capacitive coupling of the gate terminal with the MT2 terminal, which lets currents into the gate in response to a large rate of voltage change at MT2. One way to cope with this limitation is to design a suitable RC or RCL [[snubber]] network. In many cases this is sufficient to lower the impedance of the gate towards MT1. By putting a resistor or a small capacitor (or both in parallel) between these two terminals, the capacitive current generated during the transient flows out of the device without activating it. A careful reading of the application notes provided by the manufacturer and testing of the particular device model to design the correct network is in order.  Typical values for capacitors and resistors between the gate and MT1 may be up to 100&nbsp;nF and 10&nbsp;Ω to 1&nbsp;kΩ.<ref name="AN3008"/> Normal TRIACs, except for low-power types marketed as ''sensitive gate'',<ref name=2N6071>{{cite web |url=https://www.littelfuse.com/~/media/electronics/datasheets/switching_thyristors/littelfuse_thyristor_2n6071_d_datasheet.pdf.pdf |title=2N6071A/B Series Sensitive Gate Triacs |publisher=Littelfuse |access-date=January 9, 2023}}</ref> already have such a resistor built in to safeguard against spurious dv/dt triggering. This will mask the gate's supposed diode-type behaviour when testing a TRIAC with a [[multimeter]].

In datasheets, the static d''v''/d''t'' is usually indicated as <math> \left (\frac{\operatorname{d}v}{\operatorname{d}t}\right )_s </math> and, as mentioned before, is in relation to the tendency of a TRIAC to turn on ''from the off state'' after a large voltage rate of rise even without applying any current in the gate.