Is the MMA9553L compatible with an I2C bus operating at 3.3V levels?

[timjames]

The abs. max. ratings table in the datasheet gives Vdd+0.3 as the maximum permitted input voltage but also lists a 20mA clamp diode current limit.  Does this mean that I can exceed the max. input voltage provided the current is limited to << 20mA?  If so then this implies I should be able to pull the SDA and SCL inputs up to 3.3V with, eg, 4k7R resistors.  Does this seem reasonable?  In our final design we will translate the logic levels 'properly' but for development purposes we are interesting in connecting the MMA9550L module from the evaluation kit to existing hardware so we can get a head start on software development.

[reyes · Accepted solution]

Hi Tim,

Unfortunately no, you cannot connect the pull-up of the MMA9553L I2C lines to a 3.3V level, this would cause I2C communication issues and can cause permanent damage to the MMA9553L, for this case, if your MCU is using 3.3V in the I2C lines, then you must have an I2V Voltage level translator between the accelerometer and the MCU.

You can find different NXP I2C voltage level translator options here.

Have a great day,
Jose

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