DAC7578: Change I2C address after Power-Up

Hi Matthias,

I believe we will need to consult someone from our design team to understand better exactly how this was implemented. Someone from my team will take charge of that and should be able to give you an update at least for where we are on that effort by COB Friday.

Thank you in advance for your patience.

Hi Matthias,

Thanks for reaching out. While I am checking this with the design team, I would like to have some doubts clarified.

1. Are you using only the HIGH and LOW states for the address pins or the floating states as well?
2. I know you are probably using the board inside a rack, is there any possibility of getting some scope shots of the I2C and ADDR pins?

Regards,
Uttam Sahu
Applications Engineer, Precision DACs

Hi Uttam,

thank you for the quick response.

1. We need all tree states.

2. You're right it's a rack configuration. Can you specify that a little bit more

-normal communication?

-At the Moment of the hot plug procedure?

Thanks

Greetings Matthias

Hi Matthias,

My question was whether you get the problem with address pins only when they are in floating configuration or do you get the failure in GIGH and LOW states as well.

Regarding the rack configuration, I wanted to know whether you will be able to probe the address pins or not.

It will be good if you could probe these pins and see what happens when there is a communication failure.

Regards,
Uttam

Hi Matthias,

Do you have any update on this?

Regards,
Uttam

Hi Uttam,

>My question was whether you get the problem with address pins only when they are in floating configuration

>or do you get the failure in GIGH and LOW states as well.

Only with the floating state.

I worked on the delay circus now it works good. Just to be save i still would like to reset the address after power up.

 Is there a way to update  the I2C address after the power up or is the description wrong in the datasheet ?

"The device address can be updated dynamically between serial commands"

Thanks

Greetings Matthias

Hi Matthias,

My apologies for the delay in the response. We have seen some issues previously when the address pin is left floating state due to noise at system level. Is it possible for you to tie the pin to a mid-voltage using pull-up and pull-down and check whether the issue is appearing on or not?

Regards,
Uttam

Hi Matthias,

Do you have any update on this?

Regards,
Uttam

Hi Uttam,

sorry for the late response wasn't in the office for the week.

I will try it out during the week and will report.

Thanks

Greetings Matthias