Explanation of attached schematic:
I have a battery supply at 36V, which goes trough my power supply board to engines in my application.
36V also powers the switching mode converters, there are two of them, each at 5V. One of them is used to power up board with digital circuits, where also an ADC an uC are located. SMPS's are isolated.
My question is:
What is the best way to measure high voltage, high current noisy power line voltage, without coupling the noise to 5V logic power bus?
Do I necessary need to reference the logic 5V ground to main battery ground?
I have found an isolating amplifier (avago hcpl-7800), however it also needs 5V@30mA power on both isolated sides.
I have thought about serial linear regulators and powering it up directly from 36V, however it doesn't look as a wise solution.
I guess the problem is something about common mode voltage and correct referencing... however, I'm a newbie.
I'll be gratefull for help on this particular problem, also for suggestions for literature
which could help me understand my problem better
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Also, hello to everyone on the forum! Till now I was just a reader, however time has come to ask a first question.
So please forgive me if I made any mistake in forum etiquette, I'm open to any suggestions in improving my topic
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