The Renesas NEPOC PS2502L-1-K-A is a single-channel Darlington-output optocoupler in a 4-SMD gull wing package, designed for applications requiring galvanic isolation up to 5000 Vrms. Its key distinction is a minimum current transfer ratio of 2000% at just 1 mA forward current — meaning a 1 mA LED drive can switch a 200 mA load on the output side, which is a practical gain for driving relays, solenoids, or PLC inputs without a separate driver stage. The output Darlington transistor is rated for 40 V and 200 mA continuous, with a Vce saturation of 1 V at that current.
2000% CTR — why that matters for the drive budget
A minimum CTR of 2000% at 1 mA forward current means the output can sink 20 mA for every 1 mA of LED drive, worst-case. In practice, a typical microcontroller GPIO sourcing 2–3 mA can comfortably saturate the output transistor at 200 mA load, leaving margin for LED aging and temperature derating. The 1.17 V typical forward voltage is standard for an infrared LED, so the drive resistor calculation follows the usual (Vcc - Vf) / If formula.
Package and mounting — surface-mount gull wing for automated assembly
The 4-SMD gull wing package (supplier device package 4-SMD) is a standard surface-mount footprint for optocouplers, compatible with reflow soldering processes. The gull wing leads provide good coplanarity and visual inspectability after soldering. No through-hole or additional heatsinking is needed for the 200 mA output current at 40 V, as the Darlington's saturation voltage keeps dissipation low at 200 mW worst-case (1 V × 200 mA).
Active lifecycle and compliance — no LTB risk
The NEPOC series from Renesas is a mature optocoupler family with broad distribution support, which helps with supply continuity.