The 6N138W: Sourcing this part now runs through independent distribution and surplus channels. Availability is lot-specific and confirmed at RFQ — no stock-holding claim is made here.
Key parametrics for BOM fit
This is a single-channel optoisolator with a DC input and a Darlington with Base output. The minimum current transfer ratio (CTR) is 300% at a forward current of 1.6 mA, meaning the output can sink significantly more current than the LED drives — useful for driving logic inputs or relays directly from a low-current signal. Switching speed is specified at 1.5 µs turn-on and 7 µs turn-off typical. This is not a high-speed digital isolator; it suits low-frequency signal isolation, status feedback, and DC-level translation where the 7 µs fall time is within the system timing budget. Rated for 2500 Vrms isolation, the 6N138W provides basic galvanic isolation between input and output circuits in industrial control, PLC I/O modules, and motor drive feedback paths where the operating voltage does not exceed the isolation rating.
Supplied in Tube packaging, the 8-DIP (0.400", 10.16mm) body width requires a 0.100-inch pitch through-hole layout. The 8-MDIP supplier device package is the same mechanical outline — confirm the hole diameter and pad spacing against your existing DIP-8 footprint. Maximum forward current (If) is 20 mA DC; the typical forward voltage (Vf) is 1.3 V. The output side can sink up to 60 mA per channel at a maximum output voltage of 7 V — the Darlington pair provides high current gain but limits the output voltage swing to 7 V, so it cannot drive 24 V logic directly without an external pull-up or level shifter.