The Renesas NEPOC PS2841-4A-F3-AX is a quad-channel transistor-output optocoupler in a 12-BSOP package. Four isolated DC-input channels in a 4.40mm-wide body.
Rated at 1500Vrms, this is basic isolation — not reinforced. It's fine for functional isolation between logic-level domains in the same enclosure, or for breaking ground loops on a 24V sensor bus. Don't spec it for mains-primary-to-SELV separation where you need 3000Vrms or 5000Vrms reinforced. The 20µs rise and 110µs fall times mean it's a DC-level or low-frequency signal part — think status indicators, fault flags, relay coil drives, or slow digital inputs on a PLC. Not for SPI or UART isolation above a few kHz.
CTR spread 100% to 400% — design the LED drive for the minimum
Current transfer ratio spans 100% minimum to 400% maximum at 1mA forward current. That's a 4:1 spread across temperature and manufacturing. Design your input-side LED current for the worst-case 100% CTR — at 1mA If, you get at least 1mA output drive. If the load needs 5mA collector current, plan on 5mA If minimum. The 1.1V typical forward drop is standard for an IR LED. Maximum continuous forward current is 20mA, so there's headroom for a higher-drive margin if the CTR drops at cold temperature.
Rated -40°C to 100°C operating — industrial temperature range. The 300mV max Vce saturation at rated current keeps dissipation low per channel.
Active product status — Renesas still manufactures this NEPOC series optocoupler. ROHS3 compliant per the ledger. The 12-BSOP package is MSL-rated per the standard bake-and-reflow profile; verify the specific MSL level on the latest Renesas packing label if your reflow line runs lead-free peak temperatures above 245°C.