LSM303D Power - 5V vs. 3V

Support Sensors
1

I’m about to hook up the LSM303D to an Arduino micro. the description says it will accept 2.5 - 5.5V since it has its own on-board power regulation.

What I am wondering is since I have 3.3V out available on the Arduino would it be better to just use that? Run cooler, consume less power, etc… than running it off the 5V?

I’m already running the OLED display on the 5V, but I’m not sure if it makes that much of a difference. It will be for a sealed, battery powered application, so it’s important to maximize the run time while minimizing the size of the battery needed.

2

I suppose if you have 3.3V available you could use it. It won’t make a difference. Even efficiency-wise, you’ll be using either one regulator or another.

3

That’s essentially what I was thinking that it was 6, one half dozen of the other. I wasn’t sure if one might be more efficient than the other.

Appears to work fine on the 3.3V connection. Thanks.

4

Hello.

Which Arduino Micro are you using and what voltage are you running it at? If you are using the official Arduino Micro, it operates at 5V, and the I2C communication pins expect 5V signals. Without powering the LSM303D carrier with 5V, you will only receive a 3.3V signal from the accelerometer (which might still work as 3.3V should be read as HIGH by the Arduino). To ensure proper level shifting, I recommend powering the carrier with 5V if you are using it with a 5V device.

- Jeremy

5

Yes, I’m using an official Micro. I swapped it over to the 5V output and that seems to work fine also.

Thank you!