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DRV425: differential gradient field measurement circuit: Problem with Equation for common magnetic field voltage

Part Number: DRV425

Hello,

I am currently working on a bus bar application of the DRV425 with the differential gradient field measurement circuit shown on page 27 of the datasheet.

My application has for example compensation currents of I1 = 5,734 mA and I2 = -2,074 mA. I chose for R1 and R2 resistors with 85 ohm and my R3 has 80 ohm. I calculated the voltage across R1 and R2 with Equation 4 on page 22 of the "Bus Bar Theory of Operation" document and got 1,327 V as result. I also made a small simulation in Tina ti with my values where I measured half the voltage. If I calculate the voltage with V_CM = (I1*R1)-(I2*R2) I get the same result as in the simualtion.

Am I making a mistake or could the Equation be wrong?

Thank you in advance!

Best Regards 

Albin