How to use HMC5983


I have some doubts regarding the connection of HMC5983 with a flight controller.

If I want to use I2C, do I have to connect I2C/SPI pin and CS pin to VDD (= 5V in my case) or just the I2C/SPI pin?

If I use the connector in the upper part of the board, should I have to set I2C/SPI and/or CS pin to VDD?

Thank you in advance :slight_smile:


Can you please specify what board you are using, we have lots with HMC5983 :slight_smile:

Firstly, you shouldn’t supply 5V directly to HMC5983, as you can see on the datasheet :

Our boards have 3.3V regulators so that is fine, but make sure to also use 3.3V on logic levels, or use a logic-level-converter if the board you want to connect with uses 5V.

Regarding pin configurations, if you want to go with I2C, then CS and I2C/SPI should be tied to VDDIO/VDD.

Hope it helps.

Sorry, I didn’t know you have several HMC5983 boards. I have the one that it is currently sold. I want to supply it with 5 V but using 3.3 V logic levels as you mentioned.

If I understand it properly, I have to tie CS and I2C/SPI to 5V for using I2C (even if I use the JST connector), right?

Thank you for your quick and good reply :slight_smile:

Actually with that board you do not even need to do anything, CS and I2C/SPI are already pulled-up. Otherwise they should be connected to 3.3V.