Hi there,
We are using INA240A3D as a current sensor to measure a machine consumption (max 1200W). In a real case scenario, I would be using the power net (230VAC //50 Hz) to power the machine, but in this case I wanted to control the current flowing in the Rshunt so I basically used a DC power supply and shortcutted the output so I could fix the wanted current.
My Problem:
When measuring the current flowing though the Rshunt I get this weird Spurious signals and I would like to know the reason for this, as the inputs look quite smooth:
As you can see, the spurious signal disrupts my readings and therefore makes understanding signals less robust. Could you please provide some advice in order to help me figure out what's happening?
Design:
This is how the INA240 is connected to measure the current flow:
Specifications of the Test System:
- I have 2 power sources feeding into my board. A 3.3V digital signal coming from a USB and powering the digital part (module esp32), and a 200mV//3A analog signal connected to the RShunt.
- During the test the signal ISEN_OP was cutted to isolate the output from other possible external interferences.
- Live Relay signal comes from the VCC of the power Supply and the Power Relay is directly connected to the GND of the power supply.
- All GND and 3v3 are connected to Vcc and Gnd of the USB.
Thank you in advance for your help! :)
