VNF9Q20F Grounding

[TH3221]

From the application schematics of VNF9Q20F, seperating my ground planes for CReg and DVcc but wouldnt DEV_GND (straight from the VNF9Q20F at the bottom) be connected as well instead of to battery ground? Shown as the drawn orange connection. Or both?

 

[AScha.3]

Because from ds :

you should connect pin17 to ground plane , same as the cpu. And to (car) gnd(chassis) of course. 

Separating ground plane is no good idea, except for low noise analog circuits. (you dont have here - right?)

[TH3221]

Your right no low noise analog circuits, unless I would assume this chip would have something like that built in like for the current sense maybe? I just am trying to figure out why they would have separate grounds in the application schematic then?

You can see GND and DEV_GND? I've read the datasheet over and over and didn't see a reference to it

[AScha.3]

What you expect ? New physics ? Something working without solid gnd level , as good as possible ?