High-voltage Darlington optocoupler for industrial isolation
The Toshiba TLP387(TPR,E is a single-channel DC-input Darlington-output optocoupler rated for 5000Vrms isolation, making it a fit for galvanic isolation barriers in motor drives, industrial PLCs, and medical power supplies where the primary and secondary sides must be electrically separated. The Darlington output gives a minimum current transfer ratio of 1000% at 1 mA forward current, so the LED drive current can be kept low — useful when the primary-side controller has limited drive capability or you want to minimise power draw across the isolation boundary.
Turn-on time is 50 µs typical, turn-off 15 µs typical, with rise and fall times of 40 µs and 15 µs respectively.
Package, footprint, and storage notes
Housed in a 6-SOIC package with 4 leads (0.173" body width, 4.40 mm body height) — the standard small-outline footprint for medium-power optocouplers. The 4-lead pinout is the same as many Toshiba and competitor Darlington optocouplers in this package class, so a layout done for a TLP388 or similar will accept the TLP387 with no board change. The part is surface-mount only.
The 110°C ceiling is below the 125°C typical of automotive-grade parts, so for under-hood or high-temperature industrial applications verify the junction temperature stays within the limit at full load. The 5000Vrms isolation rating is a reinforced isolation level per IEC 60747-5-5, suitable for medical (MOPP) and industrial (basic/reinforced) isolation barriers.
The ROHS3 status means it is fully compliant with the latest EU RoHS directive, including all phthalate restrictions.