ADV7391 Vddio question

Hi,

We are checking with part specialist on this question and update you soon

Best Regards,

Jeyasudha.M

I was able to find Datasheet Page 8, DIGITAL INPUT/OUTPUT SPECIFICATIONS—1.8 V

"When VDD_IO is set to 1.8 V, all the digital video inputs and control inputs,
such as I2C, HS, and VS, should use 1.8 V levels."

I am assuming this means when VDD_IO is 2V5, all above would also be 2V5.

Patrick

Hi,

The VDD_IO supply powers the I/O buffers within the chip. So it powers both the input and output buffers. The comment above is also correct, although i would point out that operating VDD_IO @2V5 is not recommended.

Best Regards,

Anthony

Hi Anthony,

Thanks for the reply.  Regarding VDD_IO limits, Table 3 has VDD_IO min as 1.71V, Typ as 3.3V, and max as 3.63V.  Is this an error in the datasheet? 

Hi,

No this is not an error in the datasheet. VDD_IO can be operated at either 1V8 or 3V3. When operating at 3V3, the voltage limits are between 2.97V to 3.63V and when operating at 1V8 the voltage limits are between 1.71V to 1.89V. This is why the max/min ratings in the datasheet for this supply have the wide margin. The caveat with running the part @ 1V8 as opposed to 3V3 is that the I2C, HS and VS signalling all need to be operated at 1V8 levels. See P8 of the ADV7391 datasheet for more information regarding this.

Best Regards,

Anthony