3750Vrms galvanic isolation for industrial signal paths
The Toshiba TLP185(GRL-TL,SE is a single-channel DC-input transistor-output optocoupler rated for 3750Vrms isolation.
CTR range and LED drive — sizing the input resistor
The CTR is specified at 100% minimum and 200% maximum at a forward current of 5 mA. That spread means the output transistor can sink between 5 mA and 10 mA with 5 mA LED drive — enough to pull a logic input low or drive a low-power relay directly. If your design needs a guaranteed minimum output current at a lower LED current, the 100% floor at 5 mA is the number to design to; the 200% ceiling just means you might get more gain than expected, which is usually fine for saturated switching.
The typical rise and fall times are 2 µs and 3 µs, with turn-on and turn-off times both at 3 µs — fast enough for 100 kHz switching or isolated serial data at 115.2 kbps, but not for high-speed isolated SPI or CAN. For sub-microsecond isolation, you'd step up to a digital isolator or a high-speed optocoupler with a logic output.
Output ratings — 80 V, 50 mA ceiling
The output transistor is rated for 80 V collector-emitter and 50 mA continuous current. That 80 V ceiling covers 48 V industrial buses and 24 V logic rails with plenty of margin. The 300 mV Vce(sat) max means the output drops less than a third of a volt when saturated at the rated current — clean logic-level switching even with a 3.3 V pull-up. The 50 mA absolute-max forward current on the LED side matches the output current limit, so you won't overstress the input driving the output to its maximum.
The ROHS3 status covers the full substance restriction list, including the four phthalates — no exemption paperwork needed for EU-market equipment.