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By secavian
#182430
I have an Arduino Pro Mini 328 5v/16Mhz which I want to use with the MPU-9150 breakout (9DOF IMU). I've set up a proto board with the IMU using the LD1117V33 voltage regulator with a 3.3v output and a bi-directional logic level converter.

I am able to test the IMU by attaching it to my regular Arduino Uno R3, no problem. I use the dedicated SDA/SCL lines and digital pin 2 for the interrupt signal. Everything is fine.

I was looking over the schematic for the Pro Mini which uses the A4/A5 pins for the I2C connection. The schematic shows two "optional" pullup resistors for I2C lines. Do I need those resistors? If so, what value should they be? The schematic implies they should be inserted in-line with the logic level converter pins. Is that correct?

Thanx,
By simodk
#182571
If you haven't used resistors when connecting the IMU to the UNO, you don't need them with the Pro Mini neither.
Last edited by simodk on Wed Jun 10, 2015 1:43 am, edited 1 time in total.