Hi Everyone,
I am using INA826 for current measurement. Input SHUNT_A and SHUNT_B is connected to 100R resistor for current 0-10 mA.
I have problem because when current circuit is open (current is equal to 0 mA) a have output offset 21 mA on INA826.
INA286 is powered -5V to (-26) V.
When i use for simulations TINA software this problem doesn't exist, everything will work ok.
All devices is connect to the same GND.
Hi Filip,
I have problem because when current circuit is open (current is equal to 0 mA) a have output offset 21 mA on INA826.
The input connection to the INA826 has to be connected to establish a proper common mode voltage, Vcm. Since you have +26Vdc/-5Vdc as Vcc and Vee, the Vcm = GND =0 is ok, but the input can not be floating.
I simulated the circuit in Tina. Please keep the input capacitance low. The circuit has the differential mode LPF at approx. 8kHz, I left the same by changing R and C. Also, I add common mode LPFs.
The Vref node needs to be low impedance, <1-5 Ω impedance for the part. You may connect it GND since you have dual supply rail. The Vout's transfer function is Vout = Gain*Vdiff + Vref, where Vref = GND = 0V in the simulation, and Gain = 1 V/V.
Here is the INA826EVM user's guide, please check it out.
If you have other questions, please let me know.
Best,
Raymond
