TPS55289: TPS55289RYQR No ACK on I2C SDA line

Hi Muni,

Thanks for reaching out.

Have you checked if VCC is good?

Can you share the waveforms of SCL and SDA?

BRs,

Bryce

Hi Bryce,

Please find the waveform. We have 3.3V to 1.8V level translator for I2C. I captured at 1.8V side. But the waveform is similar at 3.3V level also.

The ACK bit is always high.

HI Bryce,

My VCC_In is 24V, We pulled Enable to 24V through 100K. Will it cause any issue? Please let me know

Thanks,

Muni

Please find the waveform of I2C clock and data

Hello Bryce,

Kindly let me know if you have any updates on below request.

thanks,

Muni

Hi Muni,

1. The max voltage rating for EN pin is 20V, 24V is over the abs max voltage of EN pin. Recommend to add the resistor divider at EN pin.

2. What is the VCC pin voltage when you send the I2C commands?

BRs,

Bryce

Hi Bryce, 

1. I placed a 150K ohm and 120K resistor devider at enable pin. I can voltage of 10V at Enable pin when VCC_In is 24V.

2. I see 5.1V at the VCC pin when i send the I2C commands.

I replaced the chip with brand new chip. I am still not able to see the acknowledgement.

Hi Bryce,

Can you please send TPS55289EVM board file. I would like to check the layout once, Since EVK is working well for us.

I already sent a friend request to you. Please accept.

Thanks,

Muni

Hi Muni,

Bryce is OoO today. Please expect a late response.

Regards,

Mulin

hi Bryce,

Please share the EVM board file.

we need your support for reviewing our schematic and board.

Kindly share your contact details like e-mail ID to discuss further.

Thanks,

Muni

Hi Muni,

I have shared the EVM board files with you on message, please check that.

Can you share the layout screenshots of TPS55289 part on each layer?

For better project progress follow up, it is recommended to keep the discussion on the E2E thread, for any project file you don't want to post on E2E, you can share with me on message.

BRs,

Bryce

Hi Bryce,

I shared the layout screenshots. ( I sent a personal message). Kindly check and let me know

Thanks,

Muni

Hi Muni,

Can you help check the marking of the device you are using?

From the layout, I don't see issue which an prevent the I2C working.

BRs,

Bryce