confirm.....ade7754 interfacing to controller

HI all...

I'am interfacing ade7754 to my C8051F120 controller.
I have bought a evaluation kit with which i got familiar with.
The ade7754 is having 2 power supplies AVdd and DVdd.

The problem is :
I have connected THe SPI pins and a reset and irq pin is also needed
to interface with controller.

I need to know weather it is needed to short the grounds of the two devices.
Another problem is the cygnal kit is having 3.5volts as power supply.
but my ade7754 has 5V.

I guess using some buffer will do...But will there be much problem if i short the two grounds directly??
Suggest me a method to interface these two things...I'am sending a schematic. You can make corrections for that and post it in your reply.

Thanking you
Venkatesh T.K
India

Hi,
You need at least to connect the digital GND to the 8051 logic GND, thats why you have it. You'll need to check that the I/O on the 8051 is 5V compatible, and that the 7754 is 3.3v compatible. This is listed in the respective datasheets.
I would suppose that the datasheet for the 7754 gives some sort of recommendations for connecting the analogue GND to the digital or not.

Most of the things you wonder about can be found in the datasheets, reference manuals, in application notes or in reference designs from the manufacturer.

TOK

Thanks GOrgon...

Thank you GOrgon....

You were absolutely right.
I got the solution from the datasheet.
And what i did was to ....
short the digital grounds.
That worked.
Now my controller speaks to ade7754.

Thanks a lot for your concern
Venkatesh T.K
India