5000 Vrms isolation in a 4-pin SOIC
The Toshiba TLP385(TPL,E is a single-channel transistor-output optocoupler in a compact 6-SOIC package with only 4 leads populated. It provides 5000 Vrms of galvanic isolation between a DC-input LED and a phototransistor output, making it a straightforward choice for breaking ground loops in industrial controls, PLC I/O modules, and isolated sensor interfaces. The output transistor can handle up to 80 V and 50 mA continuous, so it can drive small relays or logic inputs directly without a buffer stage.
CTR range: 50% to 600% at 5 mA
The current transfer ratio spans 50% minimum to 600% maximum, both specified at 5 mA forward current. That wide spread means the same part can work with a low-drive GPIO (50% CTR requires 10 mA on the LED to guarantee 5 mA output) or a high-efficiency design where 1 mA LED current still switches the output. The 300 mV maximum Vce saturation at the output keeps voltage drop low when driving a logic input.
Switching speed: 2 µs rise, 3 µs fall
Typical rise and fall times are 2 µs and 3 µs respectively, with turn-on and turn-off both at 3 µs. That places this part in the general-purpose optocoupler class — fast enough for 100 kbps data isolation or 50/60 Hz AC zero-cross detection, but not intended for high-speed digital buses like CAN or RS-485. For those, you would look at a logic-output or high-speed optocoupler.
Temperature range: -55°C to 110°C
Rated for -55°C to 110°C operating ambient, this optocoupler can live in outdoor telecom cabinets, engine-bay electronics, or factory-floor enclosures where the temperature swings wide.
Active lifecycle, no EOL concern
It is RoHS compliant per the listing.