The Toshiba TLP185(TPL,SE) is a single-channel DC-input transistor-output optocoupler in a 6-SOP package. The transistor output can switch up to 80V at 50mA, which covers most logic-level and low-power load interfaces.
The current transfer ratio spans 50% (min) to 600% (max), both specified at 5mA forward current. That wide spread means the same part can work in a low-drive digital input (where you need high CTR to guarantee logic high with a small LED current) or in a higher-drive relay coil interface where CTR margin is less critical. The 50% floor at 5mA If ensures the output transistor turns on solidly even at the low end of the batch distribution.
Rise and fall times are 2µs and 3µs typ.
The 6-SOP body (4.40mm width, 0.173" pitch) is a compact SOIC-style footprint with four active leads. It's a surface-mount part.
The TLP185(TPL,SE) is a current-production Toshiba part, available through independent distribution.