The PS8501L3-E3-AX: The Renesas NEPOC PS8501L3--AX is a single-channel DC-input optocoupler with a phototransistor output that includes a base connection. The base pin allows the designer to tailor the switching threshold or add a resistor to improve turn-off time beyond the typical 350ns — a useful degree of freedom not available on Darlington or simple phototransistor optos.
Typical turn-on of 220ns and turn-off of 350ns place this part in the fast-switching class for a phototransistor optocoupler. If you are replacing a slower opto in an existing design, check that the minimum CTR of 15% at 16mA forward current still meets your logic-level threshold at the output load — the CTR is specified at 16mA If, so plan the LED drive resistor accordingly. The output transistor is rated for 35V Vce and 8mA continuous output current. That 8mA per channel is enough to drive a CMOS gate input or a small relay coil with a base resistor, but not a heavy load directly.
Package and temperature grade
Housed in an 8-SMD Gull Wing package, the PS8501L3--AX is a surface-mount part. ROHS3 compliant per the listing, so no exemption issues for EU or similar regulated markets.
Sourcing and lifecycle
Renesas lists this part as Active.