SparkFun Forums

[sbeeram]

I want to use 8-10 LiDAR sensors (each consuming 165mA). From what I understand, if I use 5V 2A USB c supply to the redboard I can have sensors limited to 2A current consumption, however, it is unclear if I can just daisy chain these 10 sensors through the qwiic connector or if I use a qwiic I2C mux, the current limit for the mux is not mentioned in the documentation, just the operating voltage. Any clarification?

[TS-Russell]

The voltage drop would be too much to daisy-chain them all, but using the mux is possible...qwiic wires are 28AWG, so they should be good, and you're just limited to the amount of current the traces in the PCBs themselves can carry (~2A)

10 Lidars is a lot, though, especially if you run into timing issues that result in simultaneous spikes in power draw...so you might need to use 2x setups (second ATP and 2nd mux) for that many (post back how many you were able to time/run concurrently!)

[paulvha]

The 3v3 for the QWIIC connector on an Artemis ATP is provided by the LDO AP2112-3.3, which can deliver a maximum output current of 600mA. (https://cdn.sparkfun.com/assets/a/8/c/1 ... is-ATP.pdf) A mux is used for other reasons ( like connecting multiple sensors with the same I2C address) but will not improve the maximum power consumption. I am afraid there is NO way you can use the proposed setup. Consider using a strong external 3v3 supply instead of the 3v3 from the ATP.

[ReahaTaul]

Some LiDAR sensors may allow configuring unique I2C addresses. If yours do, daisy chaining with proper addressing might work for up to 4 sensors depending on their total current draw.
If your sensors share an I2C address or you need more than 4, then an I2C Mux is necessary. You'll need to consult the specific Mux datasheet to confirm its current rating, but it should be sufficient for I2C communication.

Possible Solutions:

Reduce the number of sensors: If possible, limit the number of LiDAR sensors to 4 and daisy chain them with proper addressing.
External Power Supply: Use a higher-rated external power supply (e.g., 5V 4A) to handle the combined current of more sensors.
I2C Mux with Separate Power Supply: Use an I2C Mux to koows manage sensor communication and a separate power supply for the LiDAR sensors themselves.