The FOD2741CT: Rated for 5000 Vrms isolation, the part provides galvanic separation between input and output circuits — suitable for industrial signal isolation where safety isolation is required between control and power domains. Current transfer ratio (CTR) is specified at 100% minimum to 200% maximum when forward current is 10 mA, meaning the output transistor can sink between 10 mA and 20 mA under that drive condition. Output current per channel is rated 50 mA maximum, with a Vce saturation ceiling of 400 mV.
The 8-DIP body (0.400-inch row spacing, 10.16 mm width) is a legacy through-hole footprint — the 8-MDIP supplier device package variant shares the same mechanical outline. Tube packaging is standard for this form factor. For a replacement in a through-hole board layout, any single-channel DIP-8 optoisolator with matching pinout and 5000 Vrms isolation can be considered, but pin-compatibility must be verified against the original BOM position — onsemi lists no direct cross-reference.