Hi,
I'm working in the train sector and I'm searching for a new RS-485 transceiver. It would be used in a CAN-based bus called MVB (Multifunction Vehicle Bus). The standard (IEC 61375-3) states, that the receivers in the MVB-Bus need a noise immunity of +/- 100mV. In RS-485 transceiver datasheets the values Vit+ and Vit- (Positive/Negative receiver differential input voltage) are specified. To fulfill the standard either Vit+ has to be higher than +100mV or Vit- has to be lower than -100mV. In most cases there is no Min/Max value specified. Also the Hysteresis must be between 50mv and 200mV.
The closest device I found would be the SN65HVD75 . It would achieve a minimal noise immunity of +/- 70mV with a 50mV hysteresis.
Are there any other devices that would fit my requirements? (Maybe in development …) Also it would be nice if there is an isolated device so I don't need to add a separate isolator (Closest I found: ISO1176).
Best regards
Roger