Adc operating voltage of XIAO ESP32C3, XIAO SAMD2,XIAO RP2040,XIAO nRF52840

Community General Info - Guidance
1

I am interested in knowing the voltage range that the analog inputs of the following development boards support:

  • XIAO ESP32C3
  • XIAO SAMD21
  • XIAO RP2040
  • XIAO nRF52840

I have some sensors that deliver their measurements up to 5V, while others are limited to 3.3V. Can anyone provide information on whether it’s possible to directly connect sensors that provide up to 5V to the analog inputs of these boards for measurements?

Thank you for your assistance!

2 
XIAO ESP32C3     2500mV
XIAO SAMD21      VDD
XIAO RP2040      VDD
XIAO nRF52840	 VDD

I think you need an attenuator.

3

Thanks for your answer, so only the Xiao ESP32 C3 needs the attenuator? Not these others?
XIAO SAMD21
XIAO RP2040
XIAO nRF52840

I am using a voltage splitter to limit the voltage to 3.3v to the Xiao esp32 C3 currently I am working only with the Xiao ESP32 C3, but I will also work with the others.

4

Yes, the input to the ESP32C3 must be attenuated to 2500mV.

https://docs.espressif.com/projects/esp-idf/en/v4.4-beta1/esp32c3/api-reference/peripherals/adc.html

5

Thank you very much for your help, I really appreciate this. I will work with this limit of 2500 mV.

6

Since all the microcontrollers mentioned operate at 3.3V logic levels, connecting sensors that provide up to 5V directly to the analog inputs might damage the microcontroller. You should consider using voltage dividers or level shifters to scale down the sensor output voltage to a safe range (0 to 3.3V) before connecting it to the analog inputs. This ensures that the sensor’s signal is within the acceptable range for the microcontroller.
Regard,
Capcut

1 Like
7

there isn’t a specific “XIAO” ESP32C3 or XIAO SAMD2. However, I can provide you with some general information about ADC operating voltage for commonly used microcontrollers.

  1. ESP32C3:
  • The ADC operating voltage for ESP32C3 is typically 0 to 3.3V. It is important to note that exceeding this voltage may damage the ADC input.
  1. SAMD21 (XIAO SAMD21):
  • The SAMD21 operates at 3.3V. Therefore, the ADC reference voltage is usually 3.3V. The ADC can handle input voltages in the range of 0 to 3.3V.
  1. RP2040 (XIAO RP2040):
  • The RP2040 operates at 3.3V. The ADC reference voltage is typically 3.3V, and the ADC can handle input voltages in the range of 0 to 3.3V.
  1. nRF52840 (XIAO nRF52840):
  • The nRF52840 operates at 3.3V. The ADC reference voltage is usually 3.3V, and the ADC can handle input voltages in the range of 0 to 3.3V.
    Regards
    pc