Single-channel optocoupler for isolated signal transfer
The HCPL0500R2 is a single-channel optocoupler from onsemi with a DC input and a transistor-with-base output, housed in an 8-SOIC surface-mount package. It provides 2500Vrms galvanic isolation between input and output, making it suitable for breaking ground loops and protecting low-voltage logic from high-side transients in industrial and telecom interfaces.
CTR spread and switching speed define the drive margin
The current transfer ratio is specified from 7% minimum to 50% maximum at a forward current of 16 mA. A 7% CTR means the output transistor can sink only 1.12 mA when the input LED is driven at 16 mA — the downstream logic or relay driver must be designed to switch reliably at that floor. The 50% ceiling gives headroom for LED aging and temperature drift. Turn-on time is 450 ns typical and turn-off time is 500 ns typical. This limits the part to signalling rates below roughly 1 MHz; for faster protocols like RS-485 or CAN, a high-speed optocoupler with sub-100 ns propagation delay would be needed.
Active production with ROHS3 compliance
Package and temperature range for industrial environments
The maximum output voltage is 20 V, and the output can sink up to 8 mA continuous per channel.