Thanks for your reply. I'm trying to understand how baude rate relates to rise (or fall) time. I had assumed that a baude rate of 100000 would require a rise time of less than 10us (1/100000) and the data sheet states that the rise time is 7.5us so I had thought it would be okay. But thinking about it now I suppose the signal needs to be in a steady high/low state for a reasonable period before switching to the opposite state as well, is that correct? Is there a way to calculate the maximum rise time you can have for a given baude rate?
I have found this chip which is think is a digital isolator that has a rise time of 5ns, would that be sufficient?
Thanks again for you help/