How does a PCB Ground Fill work as ground?

[liyin]

Is a ground fill connected to ground in any way, like a port chassis?

Current requires a movement of electrons through the copper medium, but when they reach the ground fill, where do they go if the ground fill is isolated?

 

[karesz]

PCB Ground Fill

Hi,
GND fills are all individuell to connect to the GND (plane) potencial...
Port chassie can have another GND (from incoming system) and has to connect per AC_capacity & i.e. 1MOhm parallel between both GNDs...
K.

 

[liyin]

Re: PCB Ground Fill

I'm trying to understand the theory of how a ground fill can work as ground.

I always thought DC current required a movement of electrons, how is this movement possible when the gound fill is not connected to something else (is isolated).

 

[karesz]

PCB Ground Fill

Than its not on GND potential, its "FLOATING", means- has some capacitancec to the environment(GND too), you have only some charge equalisation, not current flow=its NOT an EFFECTIVE GND surface :-(...
For effective working GND Fill you NEED OHMIC CONTACT (or current flow7same potential) to GND!
K.

 

[liyin]

Re: PCB Ground Fill

Makes more sense, I'll research those terms.

This is the circuit, it uses a ground fill (the rest of the card area) connected to header pin Vss, to reach a higher voltage (+13V) via negative voltage.

 

[karesz]

PCB Ground Fill

So,
Tnx for your pictures!
I would it change as follows:
Move R1,2 some (a raster) to right_with Q2,C2, than you can connect both GNDs between D4 / R2 too.
Second:
You can so have 3 identical length of bridges (is more economical to have same wire lengths) & eliminate the GND filling rights of X1/pins5&9 (is pin 9 on GND?)too...
Than is better to move C2 some down(a half raster minimum), so is more place to connect/short X1/pin5&9 GND fill to the rest GND...
You will so have place for short it to C2 negative polarity.
You can make more simple (with only two bridges & better GND quality) if the X1 Pin7`s line/wire will guided between hes pins 3/4&8, direct from D3&4_so will you eliminate the GND fill on these PCB .....
K.