Differential Signal to Single Ended Signal Conversion

Hi,
Im facing a problem here. I need an ADC that reads 0-20mA. The signal comes from a signal conditioner that creates a differential signal. However, a NI device with single ended inputs is much cheaper than differential inputs.
The signal conditioner already exists and I cant change that.
Im looking for something that can convert the differential signal to a single-ended signal.
I tried finding an IC that does that, but couldnt find one. Do they exist?
Maybe its easier for voltage than for current.
How is this usually done?
Best regards,
Arvel

Use a current sensing resistor and then use a current shunt amplifier.  The amplifier will amplify the voltage drop across the reistor.  From there, you can just read the output voltage with a DAQ.  Create a DAQmx scale to do the math to convert that voltage into a current reading.
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    Attachments:
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