Triac output optoisolator for mains-isolated switching
The Isocom IL420-X009 is a single-channel triac output optoisolator in a 6-SMD surface-mount package. It provides 5300Vrms isolation between the control side and the load side, with a 600 V off-state blocking voltage and a 300 mA RMS on-state current rating. The 35 µs turn-on time suits relay replacement, motor contactor drives, and solid-state AC switching in industrial controls, HVAC, and appliance power boards. No zero-crossing circuit means the triac fires immediately on the LED trigger, which is useful for phase-angle control or fast-switching applications where zero-cross delay is unacceptable.
The 10kV/µs minimum static dV/dt rating is the standout here. In an industrial motor-drive environment where fast IGBT switching edges couple back across the isolation barrier, a lower dV/dt part can self-commutate and latch the triac on when it should be off. The 10kV/µs floor gives enough margin to avoid false triggering on most 400 V bus transients. The 500 µA holding current is low enough that the triac stays latched through the zero-cross of a lightly loaded AC line, but if you are switching a very small load (below a few milliamps), you may need a bleeder resistor to guarantee commutation.