Optically isolated RS485 repeater circuit

[wonderfuliot]

Hi,

Can someone please point me to optically isolated RS485 schematic, something that uses commonly available parts?

While there are chips dedicated for this purpose however the parts may be difficult to find. RS485 is old and half duplex so it may be possible that simple circuits exist.

Thanks,
WonderfulIOT

[PieterP]

While there are chips dedicated for this purpose however the parts may be difficult to find.

What makes you say that? Analog devices seem to have multiple that are in production.

[adwsystems]

What problem are you trying to solve by optically isolating the RS485 communications?

[mikb55]

How much isolation do you need? 2kv, 20kv, 200kv?

Conceptually 3 optos, some resistors and an isolated power supply will do the job, however the exact components you need and the PCB layout design are going to vary depending on your precise requirements.