Dual-channel isolation for digital signals
The onsemi HCPL2531WV is a two-channel optocoupler with transistor outputs, packaged in an 8-DIP (0.400", 10.16mm) through-hole body. It provides 2500Vrms galvanic isolation between a DC input LED and the phototransistor output — enough for basic safety isolation in industrial control and PLC I/O modules. Each channel's current transfer ratio (CTR) is specified between 19% and 50% at a forward current of 16mA, meaning the output transistor can sink at least 3mA when the LED is driven at 16mA. This CTR range gives the designer a predictable gain margin for logic-level translation across the isolation barrier. Switching is rated at 450ns turn-on and 300ns turn-off typical — fast enough for 1 MHz digital signals or PLC input debounce filtering, but not for high-speed data buses. The output can sink up to 8mA per channel at a maximum collector-emitter voltage of 20V.
Lifecycle reality — obsolete but sourced
onsemi lists the HCPL2531WV as obsolete. For existing BOM lines that require this exact dual-channel DIP-8 optocoupler, supply is available through independent distribution — quantities are confirmed at RFQ. The part operates over the full industrial temperature range of -55°C to 100°C, so it can serve in outdoor or factory-floor equipment where the ambient temperature swings widely. The through-hole DIP package is still common in legacy control boards and prototyping.
No stock-holding claim is made — each order is sourced fresh. The part ships in Tube packaging, DC input type, transistor output. The supplier device package is 8-MDIP.