Also known as a Phototriac Coupler, a TRIAC Driver is a specific type of optocoupler that is used exclusively to provide an optically-isolated gate drive current to a TRIAC. This allows designers greater flexibility in selecting the gate drive current and isolation value desired separately from the TRIAC required. The TRIAC Driver + TRIAC combination is a common means of creating a discrete, high powered SSR.

TRIAC Drivers are composed of an input LED optically coupled to a photo-sensitive TRIAC Driver chip. Upon application on an input current (2.5-15mA, typically) the input LED shines light on the TRIAC Driver chip thereby allowing current flow through the device. This current then flows to the gate of a discrete output TRIAC and allows the load to be switched on or off.

All SSO TRIAC Drivers offer high input to output isolation, in load voltages from 400V to 800V, for both Zero Volt Cross (ZVC) and Random Phase (RP) switching. ZVC TRIAC Drivers turn on a Discrete TRIAC within a small window near Zero Volts, and thus avoid the creation of transients in the discrete Triac. In contrast, upon application of an input current, Random Phase TRIAC Drivers will turn on anywhere within the AC line cycle and are typically used in dimming applications.

SSO TRIAC Drivers are offered in 4 pin SOP, 4 pin DIP/SMD and 6 pin DIP/SMD packages.

• High input to output potential isolation (2.5 - 5kVrms)
• Low input control current (as low as 2.5mA)
• Variable load voltages (400V to 800V)
• Random Phase and Zero Volt Switching
• Offered in 4SOP, 4DIP/SMD and 6DIP/SMD packages