Jumper settings for QwiicBus power configuration - Entire System at 5V

Qwiic System
1

Hi there!

After reading the [SparkFun QwiicBus Hookup Guide I still haven’t grasped how to configure my endpoints and my midpoint when the ENTIRE SYSTEM is at 5V.

I have 2 endpoints and a single midpoint in my project. My starting endpoint is powered with 5V at VCC1 originating from my Arduino Nano. Then there is a midpoint with a 5V tolerant sensor connected using a QWIIC cable. Furthermore there is an ending endpoint also with a 5V tolerant sensor connected using a QWIIC cable. That is, I have no need for 3.3V at all.

The following is what I believe I should configure after reading the documentation.

Midpoint

The Bypass jumper on must be OPEN. The PSEL jumper should be set to 1.

Endpoints

The 0-1 jumper on the primary / first EndPoint should be OPEN but the 0-1 jumper on the terminating / last should be CLOSED.

My question is if the above seems correct and is complete. I would prefer not to activate the buck regulator at all since I won’t need the 3.3V for anything but that seems unavoidable. I guess my usage scenario isn’t very uncommon.

Thanks!!! :D](https://learn.sparkfun.com/tutorials/sparkfun-qwiicbus-hookup-guide#hardware-assembly)

2

In my scenario, it seems to work just using the midpoint and the endpoints as they arrived from the factory without altering any jumpers at all. Sensors are reporting and there’s no smoke or any hot components.

3

In my case also, but sometimes I’ve some peaks on SDA/SCL line.

Example disturbance 2 closer.png
Example disturbance 2 closer.png800×480 17.2 KB

Do you think it might be because I’ve connected 5V to 3.3V and I2C voltage level is 5V?