I planed constant power load control circuit. All parts are fully operational in computer simulation. But I want to Isolate High voltage (180V DC ) DC ground (GND 2) and low voltage (12V/3.3V DC) DC Ground (Gnd) What can be done for this? How to solve this problem?
Use a optocouplers to galvanically isolate signals passing between the low and high voltage circuits. Tough to do with analog circuitry though. You may have to rethink the design, e.g. to use a digital feedback and control loop. And, of course excellent insulation. Separate PCBs is a good idea.
Can you explain the need for the ground isolation?
his circuit works very well when one part is taken.
The system works very well when all ground are connected.
This system is flawless. The current controlling is very smooth and stable.
the current flowing through the shunt could also be measured very accurately.
So there are no errors in it, BUT
this circuit has 3 main parts ;
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esp32 DAC → non inverting amp gain is 4 (12 V DC )
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current control loop (185V DC)
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measure shunt voltage → non inverting amplifier to gain 6 ( 3.3V DC) → esp 32 ADC
These three sections are powered by under different voltage levels! I want isolate Grounds of 12V and 185V for safety.
Is it possible to use ground isolation like B1212 or any other method for this?
https://www.digikey.com/-/media/Images/ … 80d97f949c
thanks
I want isolate Grounds of 12V and 185V for safety.
What are the safety concerns? With a properly designed circuit board, good enclosure, and safe wiring techniques to any external components, there should be none.
Isolating the grounds creates many difficult problems to solve.
You can’t easily isolate the grounds as all parts of the circuit need the same ground reference. There are games you can play with optocouplers that have two photodiodes in them to isolate analog signals but that will get complex. The big question is why you want the isolation. Is it for noise? Safety? Regulatory? The solutions would be different for each.
If I had to do this, I would probably go with a SPI or I2C DAC and ADC running on the HV side and isolate the digital interface. Much easier to do.