Re: [Paparazzi-devel] i2c voltage level

[Martin Mueller]

Hi Refik,

> We have bought Drotek 10dof IMU, and the module works with 5V.  Do the I2C
> pins of drotek also work with 5V?

the board is supplied with 5V but the sensors run on 3.3V and so do the I2C
lines. An on-board linear 5V -> 3.3V regulator is used to have a clean 3.3V
supply (see imu-10dof-mpu6050-hmc5883-ms5611.PDF).

> Are the I2C pins of LPC2148 and STM32 processors compatible with 5V?

The digital LPC2148/STM32 pins are claimed to be 5V tolerant (not the LPC ADC
input pins) but it is good practice not to run them at 5V.

Never apply a voltage to any pin of a chip that is not powered through the
supply voltage.

Martin