SN65HVD23: Whether this transceiver can be used for power over communication interface application

HI Duraiselvi,

So what you are trying to do is very impractical - bordering on impossible. 

Standard RS-485 conservatively maxes out at around 12m to 13m at 10Mbps and if you take a more liberal approach (i.e. adding a lot of jitter to the system up to about 20%) you could push it about 10x farther - so 120m to 130m  - this also assumes an ideal bus setup (120 Ohm cable, 2 120 Ohm terminations with one at each end of bus). 

So even with no additional power coupling networks you wouldn't be able to push RS-485 devices to 500m at 10Mbps. The drive strength of RS-485 transceivers is largely standardized (minimum 1.5V across 54 Ohm resistor between differential outputs). You could potentially add RS-485 repeaters - but they are going to diminish your throughput pretty greatly so you would have to increase the base data-rate to ensure the proper data throughput is met. With how long the bus needs to be you would need 4 to 50 repeaters (which if you build the repeaters from discrete RS-485 transceivers (suggested repeater design) that will add 8 to 100 transceivers to the system)- but the jitter will keep adding to each link of the bus - so a larger number of repeaters would be suggested. 

While you can, but its not our current suggestion and we don't encourage designers to take that path, do PLC with standard RS-485 devices (https://www.ti.com/lit/ug/tidu993/tidu993.pdf) - its data throughput is very low. The passives on the bus are very large, and it requires that you have a special data streaming encoding in place (such as Manchester encoding) in order for the data to be coupled onto the shared bus without issue which will greatly degrade throughput of your signal. Doing PLC with standard RS-485 is not encouraged because its not a great solution (which is why we created the THVD8000 and THVD8010 because they are much better suited for PLC). However the problem with the THVD8000 (besides the need for a lot of repeaters - which is true for standard or THVD8000) is that we only spec a max data rate of 500Kbps at 5MHz modulation (but due to modulation scheme its basically equivalent to running a 10Mbps standard data stream) and you may be able to push that to 1Mbps (at the cost of additional duty cycle distortion (i.e. jitter)).

Since RS-485 is the wired long distance standard - nothing really can fit that niche except RS-485 (and RS-422 - but 422 is just a worse version of 485 so the problems would be the same there) at the bus length you need it becomes very impractical to meet the 10Mbps - this is due to the physics of the transmission line - there are going to be significant AC losses across a transmission line of 500m at the data-rates required which would require repeaters - which will create their own issues if implemented on the line. 

Why do you need 10Mbps at 500m? Is there any room to move that requirement - as generally with RS-485 you pick speed or distance - not both because they are inversely related. 

Please let me know!

Best,

Parker Dodson