So I am setting up current sensing following this hookup guide
and the chip I have is the ESP32-S3.
I have many questions I need help with:
I see that the Vref for the ADC pins are 1.1V. I believe I need the VCC voltage of tha acs723 to match that 1.1V. I also see that the ESP32-S3 does not have DAC so I wouldnt be able to use a different pin set to output, to match the voltage.
- How would you reccomend I provide power to VCC of the acs-723 to make sure it matches the Vref of the adc pin?
I also see that its possible to set the attenuation of the adc pin to read a larger voltage range. I am not sure on what the voltage range woud be if I used “12 dB” which I found on page 1446 I am even more uncertain on how I would actually set that in the code and how many other things that would affect.
- Is there value in setting the attenuation and how would I do that?
all of the information I saw about setting the attenuation was for the espressif doc in C, but with platformio in C++ and having found some examples for integrating libraries I intend to use later in this project, im not sure I really want to convert to C or if there is even any value in exploring attenuation further.
I intend to measuer currents bewteen 0 and 1500mA. If the VCC is 1.1V, I believe I would set the Vref dial so that when there is no load, it would read 0V. When I uploaded the example sketch and was reading some values while adjusting the vref knob, I noticed I was able to turn it counterclockwise past the point at which it began reading 0V. Are there any problems if its over adjusted like I noticed?
- What would the reccomendation be for setting the Vref potentiometer, and what values should I expect to read when there is no load?
For setting the gain and sensativity, with intended current between 0 and 1500mA, if I keep the 1.1V
- would the sensativity = 1.3636 (1500 / 1100) the total mA over the Vref?
- If I pass a constant current of 100mA to the acs-723, would I expect to see a voltage change of 73.33mV