Hi All,
I'm using a NANO board with a ATMEGA328p to translate a linear voltage output from a flow sensor.
Its a very simple implementation that reads the ADC pin and creates a calculated pulse signal on another pin.
When the flow sensor is picking up flow all is well and I can see the correct pulse being generated.
I've been powering the NANO off my laptop via USB. And when there's no flow, the sensor output settles at 0.35Vdc as per the datasheet.
However, when i unplug my laptop's power supply and its running off its battery only, this Zero flow output rises to 0.85Vdc.
To this effect, when i power my NANO off an external AC/DC power supply this Zero flow state puts out the higher 0.85Vdc, but when i take earth from the AC side and connect it to the DC negative, This value settles at 0.35Vdc again.
i'm not using any additional analog hardware other that the standard Arduino NANO board. Simple powering the sensor with 5V and GND from the board and landing its signal wire on ADC0.
Any help understanding this grounding potential issue would be much appreciated.
Thanks!
I'm using a NANO board with a ATMEGA328p to translate a linear voltage output from a flow sensor.
Its a very simple implementation that reads the ADC pin and creates a calculated pulse signal on another pin.
When the flow sensor is picking up flow all is well and I can see the correct pulse being generated.
I've been powering the NANO off my laptop via USB. And when there's no flow, the sensor output settles at 0.35Vdc as per the datasheet.
However, when i unplug my laptop's power supply and its running off its battery only, this Zero flow output rises to 0.85Vdc.
To this effect, when i power my NANO off an external AC/DC power supply this Zero flow state puts out the higher 0.85Vdc, but when i take earth from the AC side and connect it to the DC negative, This value settles at 0.35Vdc again.
i'm not using any additional analog hardware other that the standard Arduino NANO board. Simple powering the sensor with 5V and GND from the board and landing its signal wire on ADC0.
Any help understanding this grounding potential issue would be much appreciated.
Thanks!