What the 5300 Vrms isolation buys you
The SFH6345-X017T is a single-channel optocoupler from Vishay with a transistor output and a DC input. Its 5300 Vrms isolation rating covers reinforced isolation for industrial drives, medical equipment, and power-supply feedback loops where galvanic separation between primary and secondary is non-negotiable. The 8-SMD gull-wing package suits surface-mount assembly without through-hole compromises.
That is enough to pull a logic input low through a 10 kΩ pull-up to 5 V, but leaves little headroom if you need to drive a heavier load or a long cable. The 400 mV Vce(sat) max ensures the output rail stays clean when saturated. For designs that need more gain, look for a higher-CTR variant in the same family.
300 ns switching — not for high-speed, fine for 1 Mbps class
Typical turn-on and turn-off times of 300 ns each give a combined propagation delay around 600 ns. That supports data rates up to about 1 Mbps — adequate for isolated SPI clock, fault flags, or PWM at tens of kHz. If you need 10 Mbps or faster, a digital isolator or high-speed optocoupler is the right choice.
The 100°C upper limit is below the 125°C military-grade boundary, but the -55°C low end handles cold starts in northern climates without issue.
ROHS3 compliant, so it fits current European and global RoHS requirements without exemption paperwork.