Grove (j2) connector voltage

Official Hardware Kits Nesso N1
1

Hello Everyone!

I want to use this sensor on the grove connector: Adafruit STEMMA Soil Sensor - I2C Capacitive Moisture Sensor [JST PH 2mm] : ID 4026 : Adafruit Industries, Unique & fun DIY electronics and kits , according to the description, its data line will also use the power supply level, and since the power supply in the nesso n1 groove connector is 5v, both grove_io_0 and grove_io_1 will receive 5v.

Do I understand the nesso n1 description correctly, that this will work, all legs of the j2 connector are 5v compatible?

Thanks in advance for your answers.

2

Hi @Kutyus. The following statements from the documentation applies to all the I/O pins on the Nesso N1:

https://docs.arduino.cc/tutorials/nesso-n1/user-manual/#key-features

WARNING: All GPIO pins are 3.3 V logic only and are not 5 V tolerant.

https://docs.arduino.cc/tutorials/nesso-n1/user-manual/#voltage-compatibility-considerations

Voltage Compatibility Considerations

Before connecting any external components to your Nesso N1, it is important to understand its voltage characteristics to prevent damage to your sensors and modules:

The Nesso N1 operates at 3.3 VDC, which means:

  • All digital I/O pins use 3.3 VDC logic levels (HIGH = 3.3 VDC, LOW = 0 VDC).
  • Analog inputs can safely accept 0 to 3.3 VDC.
  • Communication pins (I2C, SPI, UART) operate at 3.3 VDC logic levels.

For 5 VDC components, you must add external level shifters for digital communication pins.

Always check your component's datasheet for voltage specifications before connecting. When in doubt, use a multimeter to verify voltage levels or add protective level shifting.

It is true that the "+5V" pin on the Grove connector provides a 5 V output, but the connector's GROVE_IO_0 and GROVE_IO_1 I/O pins are not 5 V tolerant.

3

Do the sensor not work on the QWIIC port?

4

Hi @ptillisch!

Thanks for the detailed answer, this sentence in the nesso description is ambiguous to me: "Use this connector for Grove modules that require 5V operation or GPIO control."

5

Hi @customcontroller!

That's a great idea, thanks.

6

Thanks for pointing this out. I agree. I also noticed this, as well as similar ambiguity in the user manual and tech specs content while I was investigating your request. I have submitted a report about that to the people at Arduino responsible for this documentation.

I intended to mention that in my previous reply, but I see now I forgot to do so.