the ground of om-amp

[mohammadmother]

Hi
I using AD8055AN as om-amp for feedback voltage. I want to supply of om-amp with separate battery. I simulate the circuit 1 in PSPICE properly. But the circuit 2 has error. why without ground I have error. (as we know the power supply of om-amp should be isolated).

 

[c_mitra]

The voltage source lacks reference ground.

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(as we know the power supply of om-amp should be isolated).

If the ground reference is missing the voltage at V+ and V- becomes undefined.

Only potential differences have significance; a potential of 12V at the V+ pin has meaning only with respect to the ground.

 

[KlausST]

Hi,

as we know the power supply of om-amp should be isolated

all supply voltages and signals should refer to the same potential.
They must not be isolated.

Klaus