What the 10Mbps and open collector mean for your BOM
The 6N137SD is a single-channel optocoupler from onsemi with a 10Mbps data rate — fast enough to isolate a CAN transceiver, a microcontroller UART, or a PWM gate-drive signal without introducing bit errors. The open-collector output pulls down to ground through an external pull-up resistor, so the logic-high level is set by the supply rail on the output side (4.5V to 5.5V). 2500Vrms isolation between input and output means it safely separates a low-voltage control circuit from a higher-voltage power stage or a noisy motor drive — common in industrial automation and power-supply feedback loops.
onsemi has marked the 6N137SD as obsolete. The 8-SMD gull wing package is hand-solderable with a fine-tip iron — a rework tech can replace it on a board without hot air, though the 50ns rise time means the output edge is fast enough that a clean PCB layout matters to avoid ringing.
Temperature range and board-fit
Common-mode transient immunity is 10kV/µs typical — this is the key spec for motor-drive isolation where fast switching edges couple noise across the barrier. A part with lower CMTI would glitch the output on a hard commutation event.