ADS8556: the state of DBx-pin

sorry, I missed the attached.

AD8556 example.pptx

sorry, I missed the attached.

7510.AD8556 example.pptx

Hi Noriyuki,

When the /CS signal is high, the digital bus will be in a high-Z impedance state. The BUSY on the ADS8556 is an output signal which indicates ADC's internal conversion status, so this output signal can be monitored to check whether the ADC is working properly or not. For example, the maximum conversion time is 1.26us on ADS8556, so something is incorrect if the actual conversion time (BUSY high) is longer than 1.26us after issuing a conversion start signal to the ADC.

Best regards,

Dale

Dale,

Thanks. 

If the BUSY is stuck to High level due to the certain failure and /CS is High, what if DBx-pin will be?

I think it's difficult to reply, but it will be helpful to get any comments on this.

Regards,

Noriyuki Takahashi

Hi Noriyuki,

It's still in high-Z state because /CS is high.

Best regards,

Dale

Dale,

Customer has an additional question when BUSY-pin is stuck to High.

Could you see the attached for the detail?

7510.AD8556 examplepptx.pptx

Regards,

Noriyuki Takahashi

Hi Noriyuki,

We did not encounter this specific situation, however according to my understanding and experience, the output on these data lines  under this specific condition should be valid data and  these data should remain constant when /CS is low.

Has  your customer used ADS8556? or they are planning to use this ADC?

Best regards,

Dale