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i.MX8MQ, I.MX8MM and i.MX8MN I2C clock errata

Question asked by Felix Radensky on Feb 6, 2020
Latest reply on Feb 13, 2020 by Diego Adrian Cuevas

Hi,

NXP Linux and u-boot code configure PMIC I2C bus frequency at 400KHz. See for example:

I.MX8MQ: fsl-imx8mq-evk.dts\freescale\dts\boot\arm64\arch - linux-imx - i.MX Linux kernel 

i.MX8MM:fsl-imx8mm-evk.dts\freescale\dts\boot\arm64\arch - linux-imx - i.MX Linux kernel 

i.MX8MN:fsl-imx8mn-evk.dts\freescale\dts\boot\arm64\arch - linux-imx - i.MX Linux kernel 

 

However i.MX8MQ, i.MX8MM and i.MX8MN errata state the following:

When the I2C module is programmed to operate at the maximum clock speed of 400 kHz (as
defined by the I2C spec), the SCL clock low period violates the I2C spec of 1.3 uS min. The
user must reduce the clock speed to obtain the SCL low time to meet the 1.3us I2C minimum
required. This behavior means the SoC is not compliant to the I2C spec at 400kHz.

 

Question: Can i.MX8MQ, i.MX8MM and i.MX8MN PMICs safely operate at 100KHz frequency ?

 

Thanks.

Felix.

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