TCA9509: Sharing I2C bus with TCA9509RVHR

JDJ

Part Number: TCA9509

From the datasheet of TCA9509RVHR, it appears that there is no limitation to share I2C bus with other devices. If we use some I2C device instead of another TCA9509, then we can treat upper TCA9509 as normal I2C device. Is this true? We just want to make it sure if there is any potential I2C hung up issue.

over 4 years ago

0 Chris Ayoub over 4 years ago

TI__Genius 15345 points

Hi JDJ,

I'll look at this and get back to you tomorrow.

Best,

Chris

+1 Clemens Ladisch over 4 years ago

Guru 322000 points

Yes; there can be multiple I²C devices on both A and B sides.

+1 Chris Ayoub over 4 years ago in reply to Clemens Ladisch

TI__Genius 15345 points

Hi JDJ,

As Clemens said there is no issue having multiple I2C devices share the same bus. However, what is important is making sure that the bus capacitance doesn't exceed the I2C spec. Having too high of a bus capacitance will cause issues with your rise and fall times and might make I2C communication not possible. Each device will add it's own bus capacitance to the bus so just make sure that it all aligns with the spec.

Best,

Chris

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TCA9509: Sharing I2C bus with TCA9509RVHR