SN65DSI83: I/O structure on the SDA & SCL pins

Randhir Kalsi

Part Number: SN65DSI83

Hello team,

Hope you are doing well. When you get a chance please share some feedback on below customer question:

We are trying to implement a design where the SN65DSI83 can be powered off, yet the I2C bus continues to be used for other devices. We believe that the device can be powered off and the SDA/SCL I/O can remain at 1.8V because they are open collector. I expect there are ESD steering diodes that make that a bad idea. Please let us know the I/O structure on the SDA & SCL pins. Also, what is your recommended TI I2C isolation buffer for 1.8V I/O on each side?

over 5 years ago

0 Ikechukwu Anyiam over 5 years ago

TI__Mastermind 35130 points

Hi Randhir,

The voltage ratings for these pins in the absolute max ratings do not depend on Vcc so it should be fine. For I2C buffer recommendations please consult with the TRX team.

Regards,

I.K.

0 Randhir Kalsi over 5 years ago in reply to Ikechukwu Anyiam

TI__Expert 4545 points

Thanks for the response I.K.See below customer feedback;

The SN65DSI83 does not have and ESD steering diode from SDA/SCL to VCC rail?

I need to make sure that the I2C bus does not get pulled down when the LCD (SN65DSI83) is powered down. There are other devices on the bus that have to remain active.

0 Ikechukwu Anyiam over 5 years ago in reply to Randhir Kalsi

TI__Mastermind 35130 points

Hi Randhir,

Sorry for the delay, I'm checking with design on the input structure to make sure.

Regards,

I.K.

0 Ikechukwu Anyiam over 5 years ago in reply to Ikechukwu Anyiam

TI__Mastermind 35130 points

Hi Randhir,

It looks like there aren't any ESD steering diodes. I also looked at this on the bench and did not see any issues with reading/writing to different devices on the same I2C bus while the SN65DSI83 was powered down.

Regards,

I.K.

0 Randhir Kalsi over 5 years ago in reply to Ikechukwu Anyiam

TI__Expert 4545 points

Thanks I.K.

Interface

Interface forum

SN65DSI83: I/O structure on the SDA & SCL pins