Isolation rating and signal transfer
The 6N139SVM provides 5000 Vrms galvanic isolation between input and output, suitable for breaking ground loops in industrial control interfaces and medical equipment where patient isolation is required. With a minimum current transfer ratio of 500% at 1.6 mA forward current, the Darlington output stage can drive a logic gate or microcontroller input with less than 2 mA LED drive, keeping the input-side power budget low. Typical turn-on time is 240 ns and turn-off time is 1.3 µs, which limits the usable data rate to roughly 300 kbps in a non-return-to-zero scheme — adequate for isolated RS-232, I²C, or slow SPI links, but not for high-speed CAN or Ethernet.
Output drive and temperature range
Production status and package form
Input characteristics and LED drive
The input is a DC-coupled LED with a typical forward voltage of 1.3 V and an absolute maximum forward current of 20 mA, so a series resistor is required when driving from a 3.3 V or 5 V logic output. Because the output is a Darlington pair with the base brought out to pin 6, the user can add a base-emitter resistor to adjust switching speed or tailor the CTR for a specific load — a flexibility not available in standard Darlington optocouplers.