FX3 IIC 1Mhz setting

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Anonymous
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Hi

I have a question about FX3's IIC.

I want to set IIC speed to 1Mhz.
I try after setting as below but IIC speed is about 760 Khz.

1. Set VIO5 to 3.3 V.
2. Set CyU3PI2cSetConfig funciton with bitrate 1000000.

3. Set CyU3PSetI2cDriveStrength function with CY_U3P_DS_FULL_STRENGTH.

Is there need any other setting?

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Hemanth
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First like given First question asked 750 replies posted

Hi,

The I2C frequency varies based on the Bus capacitance of SCL and SDA lines; Pull-up resistors. You have to make sure that the pull-up resistor values are less then the RpMax. For calculation of RpMax refer to section 7.1 of I2C specification which is available in the following link:

https://www.nxp.com/docs/en/user-guide/UM10204.pdf

Regards,

Hemanth

Hemanth
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