3750Vrms isolation in a 4-lead 6-SOP
The Toshiba TLP185(GB,SE is a single-channel DC-input transistor-output photocoupler in a compact 6-SOP package with only 4 leads populated. Its 3750Vrms isolation rating suits galvanic isolation in power supplies, motor-drive feedback, and industrial digital I/O where the primary side needs to talk to a low-voltage logic rail without a conductive path. The current transfer ratio spans 100% minimum to 600% maximum at a forward current of 5mA, which means a 5mA LED drive can produce a collector current between 5mA and 30mA — enough to saturate a standard TTL or CMOS input without an external buffer in most cases.
Switching speed — 2µs rise, 3µs turn-on
It handles relay coil drives, contact-monitor inputs, and status LED indicators cleanly, but it is not intended for high-speed serial isolation or PWM gate-drive feedback above a few kilohertz.
The 4-lead variant (pins 1, 3, 4, 6 populated) saves board area compared to a 6-lead SOIC while maintaining the same isolation creepage distance.