Isolation and signal transfer
The CNY1713S: Rated for 5300Vrms isolation, this opto handles reinforced insulation in mains-referenced circuits — think motor drive feedback, SMPS secondary-side sense, or PLC digital input isolation where the galvanic barrier must survive a 2.5 kV surge without breakdown. Current transfer ratio spans 40% min to 80% max at 10 mA forward current — the spread is wide enough that the downstream logic threshold must tolerate a 2:1 gain variation across the reel. The transistor output with base access lets you bias the phototransistor for faster switching or lower saturation. Typical turn-on is 2 µs, turn-off 3 µs, with rise/fall times of 1 µs and 2 µs respectively — adequate for 10 kHz switching or low-speed serial isolation, but not for high-speed data links.
6-SMD gull wing package, supplier device package 6-SMD — the 1.27 mm pitch and gull-wing leads suit reflow assembly on standard FR-4. The 300 mV max Vce(sat) at 50 mA output means the collector-emitter drop stays low enough to drive a 5 V logic input directly.