I2C extender

[a8Chcx]

Hi,

I am trying to design I2C extender.

I found two options from NXP:

P82B96 and PCA9615. Ihave the follwoing questions:

1) Both chips are active and good for the new design? If not, there is any alternative?

2) Which one is better to use? What is the major difference?

Thanks,

Christie

[diazmarin09]

Hello a8Chcx,

I hope all is great with you. Thank you for using the NXP communities.

I do recommend considering the following devices as they remain active with no plans of discontinuation:

P82B96DPZ (I2C-bus buffer)

P82B96TD,112 (I2C-bus buffer)

PCA9615DPZ

Both series are great options, anyway, could you please share more details about your requirements?

Regards,

David

[a8Chcx]

Hi David,

Thank you for your information.

My application as follows:

The I2C(MCU) master communicates with the remote board over I2C. The distance is about 1M. On remote board, there are 3 I2C slaves. There are 3 motors running around. I concerns about EMI interference. I am trying to use the following configuration. Can you tell me which one is better for my application, especially for EMI interference?

Configuration 1: P82B96: The master and remote board both are 3.3VDC logic, I am going to use the local 3.3V with 4.7K pull-up on SDA and SCL. Then use common 12VDC to power both P82B96. Can you tell me what the power consumption on 12VDC is?

Configuration 2: PCA9615: I am going to use local 3.3VDC to power VDDA and VDDB on both PCA9615. Can you tell me what the performance difference is if use common 5VDC to power VDDB on both PCA9615? Can I just use 3.3VDC for easy implementation? Can you tell me what the power consumption on VDDA and VDDB are?

Thanks,

Christie

[diazmarin09]

Hello a8Chcx,

Thank you for using the NXP community.

Both devices are highly recommended. I mean, using the PCA9615 device, the cables can be extended to at least 3 meters (3 m) or longer running at lower clock speeds. It features ESD protection that exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101. While the P82B96 device features 400 kHz operation over at least 20 meters of wire and ESD protection that exceeds 3500 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101.

In this case I would recommend performing your own test to select the best device for your application.  

I hope this information helps.

Regards,

David