The 4N39 and 4N40 have a gallium-arsenide infrared emitting diode optically coupled with a light activated silicon controlled rectifier in a dual in-line package.
• High efficiency, low degradation, liquid epitaxial LED
• 10 A, T2L compatible, solid state relay
• 25 W logic indicator lamp driver
• 400 V symmetrical transistor coupler
• Underwriters Laboratory (UL) recognized - File #E90700