Galvanic isolation for industrial signal paths
The TCET1103 is a Vishay single-channel optocoupler built for 5000 Vrms isolation between a DC input and a transistor output. That isolation rating suits it for breaking ground loops in PLC digital inputs, motor-drive feedback, and switched-mode power-supply secondary-side sensing.
Current transfer ratio is guaranteed between 100 % and 200 % at a forward current of 10 mA. A 100 % minimum means the output transistor can sink at least 10 mA when the LED is driven at 10 mA — enough to pull a 5 V logic input low through a 470 Ω pull-up without an external buffer. Typical turn-on time is 6 µs, turn-off 5 µs, with rise and fall of 3 µs and 4.7 µs respectively. This is adequate for 10–100 kHz switching in relay drivers or low-speed isolated serial links, but not for high-speed data isolation.
Active production — no end-of-life concern
The through-hole 4-DIP package has no moisture sensitivity level, so it stores indefinitely in a dry cabinet or standard shelf without bake-out requirements.
Package and temperature range for the board
The 4-DIP (0.300-inch, 7.62 mm pitch) through-hole package fits standard 0.100-inch breadboard and PCB layouts. Operating temperature spans -40°C to 100°C, covering industrial enclosures and outdoor telecom cabinets without derating. Maximum output voltage is 70 V, and continuous output current per channel is 50 mA. The forward voltage is 1.25 V typical at rated current, so a 5 V logic output can drive the LED through a 330–390 Ω series resistor.