ST's ACS Triacs, or ACST, act as a Triacs, but with an enhanced voltage-transient clamping and absorbing capability.

Both transients generated by load commutation and those coming from the mains line, such as those described in IEC 61000-4-5, are successfully absorbed by the device and the system. The clamping and crowbar function of the ACST ensure safe transient behavior for the system and the ACST. The circuit can thus be simplified, with no need for MOV or snubber circuits.

These devices have 800 V blocking capability, with standard and logic level gate choices.
They are available in Fullpack, IPAK, DPAK, D²PAK or I²PAK packages.