Part Number: TMS320F28335
Hi,
I've been generating code from Simulink for my power converters using C2000 F28335 system.
I had a problem with current readings from INA199A2 bidirectional current sensors with 2mOhms shunt resistor. I initially thought that the problem is my current sensor and even asked TI experts about potential issues.
I recently found out that the output of INA199A2 is actually correct. Unfortunately, my microcontroller does not "understand" it properly.
I run several tests under different loads. One of the probes of my oscilloscope was connected to B1 port of C2000 - this is where the signal from my current sensor was connected.
I can clearly see that ADC voltage readings of C2000 do not much with the voltage I see on the oscilloscope.
The voltage at pin B1 was always 1.65 Volts (reference voltage).
In one of the experiments my reading was initially okay for as long as other processes were not activated. I energised one of the capacitors on the PCB (no load connected to the capacitor) and value of ADC reading increased from 2270 (good value - corresponding to 1.65V) to 2510 (wrong value). The voltage at pin B1 stayed constant all the time at 1.65V which I can see on the oscilloscope.
Does anyone know why the system reads incorrect ADC value?
