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Hello,
I would like to check the reason why MBR3 require pulled-up on I2C line if the pins is unsed.
Basically, I2C should be used by pulled-up but if I2C is not used and does not connect to anything device, MBR3 is not controlled ever after even if MBR3 enter stard condition. So I think we can be pulled-down on I2C line.
Please let me know the reason MBR3 need pulled-up.
Best regards,
Solved! Go to Solution.
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The default drive mode of I2C pins is open drain - drive low, if I2C is not used the state of SCL/SDA is High-Z (with big input impedance) which is easy to couple noise from the outside to inside,
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The default drive mode of I2C pins is open drain - drive low, if I2C is not used the state of SCL/SDA is High-Z (with big input impedance) which is easy to couple noise from the outside to inside,
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Hello xzng-san,
Thanks. That right.
If the reason is only external noise, I would like to put pull-down to the I2C pins at the view point power consumption.
Is it OK?
Best regards,
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Pull down is good, just don't leave SDA/SCL pin float is fine.
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Hello
Thank you very much.
Best regards,