The EL357N-G series is a compact, surface-mount optocoupler consisting of an infrared emitting diode optically coupled to a phototransistor detector. Housed in a 4-pin small-outline package with a low 2.0 mm profile, it provides a high isolation voltage of 3750 Vrms between input and output. The series offers a wide current transfer ratio (CTR) range of 50% to 600%, making it suitable for diverse signal coupling needs. It is fully halogen-free, Pb-free, and RoHS compliant, and carries multiple international safety approvals including UL, cUL, VDE, SEMKO, NEMKO, DEMKO, FIMKO, and CQC. Typical applications include DC-DC converters, programmable controllers, telecommunications equipment, and signal transmission between circuits with different potentials or impedances.