This part is specified for operation at both 3.3 V and 5 V; recommended operation is between 3 V and 5.5V.
Based on this, is it ok to supply the part with a non stabilized supply, as long as it stays within 3 and 5.5 V as the load changes?
Or, should the supply still be reasonably stable around one value (i.e. practically, 3.3 or 5 V +- 5-10%)?
The application is isolated, so the contract design firm would like to save the cost of a stabilized isolated supply for the transceiver.
Being isolated, the RX line supplies the LED of an optocoupler so it doesn't need to respect very tight High and Low voltage levels for the receiving logic. Conversely, the TX and DE lines are driven by the output (phototransistor) section of optocouplers, so also in this case they're decoupled from the specific High and Low voltage levels of the driving logic.
However, I am still concerned that the part could not perform according to specification, or even malfunction, if supplied from a non stabilized supply.
Would it be possible to define a "minimum supply quality" requirement which reasonably allows a reliable part operation?
NOTE: Max signaling rate will be pretty low (57600 bps max).