Other Parts Discussed in Thread: INA326
Hello,
I’m currently working with the INA236, and I have a few doubts regarding its correct configuration and usage, since I find some aspects a bit confusing.
I want to measure the output voltage and current of a variable DC-DC converter using the INA236 together with an INA326, as shown in Figure 1 of my setup.
My goal is to correctly sense the output voltage, but to achieve the required measurement range, I need to configure the INA236 in common-mode operation.
Figure 1.
According to the datasheet, the shunt resistors must be selected based on the desired voltage and current ranges. However, I would like to understand what happens if I use shunt resistor values designed for higher voltage ranges than those actually present at my output.
Additionally, I’d like to confirm whether my connection setup is correct, since in Figure 2 from the evaluation board documentation, the wiring appears to be different, and I’m not sure why.
Figure 2.
I also have a conceptual question:
Could you please explain the difference between a shunt resistor and a regular resistor, and why a specific “shunt” type is required for this application? I’d like to understand how its characteristics (such as tolerance, temperature coefficient, and power rating) affect the current-sensing accuracy.
Could you please help me understand:
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The correct location and conection where I should place my load (which will be powered by the buck-boost converter).
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How to properly configure the circuit so that I can accurately sense both voltage and current at the DC-DC output.
Thank you very much for your help and any clarification you can provide.
Best regards,
Sebastián Cardona Ramírez
