Difference between GND and PGND

[Kashi]

gnd pgnd

HI, I m using a SLIC Ag1460. There are two grounds associated with it. A simple GND and a PGND (Power Ground). I want to know that are GND and PGND same or different from each other. What should i do to to connect a pin to PGND.



Timely answer to this is the key for success to my project.

 

[maziaar83]

what is pgnd

Hey man!
they are completely different!
do not connect them together! never!

 

[DrWhoF]

pgnd +

I think they have to be connected at one point.
Take a look in this PDF file at PCB layout and circuit diagram:
**broken link removed**

 

[xerxer]

p gnd

i think this relate to kelvi connetion. so you can not connect the two pad in dircect

 

[kevpat]

pgnd

Kashi, You will need to connect the grounds at a star-point usually as close as possible to the power input/output point on your pcb. This should be the only point they connect to stop large pwr GND circulating currents effecting sensitive circuitry connected to your GND plane.

 

[wichayen]

p. gnd

As datasheet that posted by DrWhoF.
PGND and GND is the same reference level. So you I think you should connect it together (by star connection).
The reason why they seperate PGND and GND is to avoid noise interference from GND to PGND. usually power circuit is low frequency and digital circuit is high frequency. You can see in datasheet that posted by DrWhoF. The inner layer2,3 of PCB seperate 2 area. because they want to connect PGND and GND only one point (star connection).

 

[kender]

difference -vss and gnd

You should connect GND and PGND at exactly one point on your board (or, may be, one point in your whole instrument). This is called "star ground", or "totem pole ground". You can find a simple diagram of the star ground here