I would like to provide two sources of power to a RS485 network and am not sure I have it right.
The physical network cable will consist of A, B, GND, and V+. The supply for V+ needs to be large enough to power the entire network.
Each RS485 interface regulates V+ to +5. Most nodes are powered by V+ using this regulator. Critical nodes will also have a small local regulated power supply, maybe 100mA.
D1 (1N4001) prevents the small local supplies from attempting to power the entire network.
Since the uC and the V+ powered regulator are both regulated to +5V there should be no problems having the two supplies? Or should I make sure that the output of the interface regulator is always a bit less then that of the uC regulator?
3v0
The physical network cable will consist of A, B, GND, and V+. The supply for V+ needs to be large enough to power the entire network.
Each RS485 interface regulates V+ to +5. Most nodes are powered by V+ using this regulator. Critical nodes will also have a small local regulated power supply, maybe 100mA.
D1 (1N4001) prevents the small local supplies from attempting to power the entire network.
Since the uC and the V+ powered regulator are both regulated to +5V there should be no problems having the two supplies? Or should I make sure that the output of the interface regulator is always a bit less then that of the uC regulator?
3v0
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