Triac couplers—basic properties and application design Application Notes 1 Rev. 1.1 2021-06-07 ©2018-2021 Toshiba Electronic Devices & Storage Corporation Introduction Triac couplers are photocouplers that have a triac output. They are commonly used for AC powered load switching applications. Triac couplers operate on AC power and differ from transistor couplers and IC couplers in several ways. This document explains the implications of differences in performance characteristics for circuit design. Triac couplers—basic properties and application design