Hello, everyone.
In the 4-20m loop circuit, taking power in signal is small, I thought about using ADA051-2 Dual OP AMP construction of differential amplifier, the attachment contains schematics, amplifying the signal to the ADUC7061 processing, diagram parameters have to be improved? I use the oscilloscope (AC ) C14 measurements to the voltage across the 20mV VPP noise ( attached figure 1), how to eliminate the noise?
Considering the sensor power changes, ADC reference source can make the sensor power source through a resistor divider get? ( Figure 2 ) I want to know that there will be what kind of impact on circuit.
Thank you