Ground Points

Hay
iam facing grounding problems
In my application I am using 3.3vfor micro controller (DGND1), 5V for digital (DGND) & analog circuit(AGND), 12V proportional solenoids(12VGND) & 24V for Solenoids(24VGND)
I am getting these voltage from 5V, 12V, 24V SMPS
My doubt is how to connect all these ground points in the circuit.

Regards
Chandu

chandu13 said:

Hay
iam facing grounding problems
In my application I am using 3.3vfor micro controller (DGND1), 5V for digital (DGND) & analog circuit(AGND), 12V proportional solenoids(12VGND) & 24V for Solenoids(24VGND)
I am getting these voltage from 5V, 12V, 24V SMPS
My doubt is how to connect all these ground points in the circuit.

Regards
Chandu

Click to expand...

Connect them at one point only, where the power supplies enter the board.

chandu13 said:

Hay
iam facing grounding problems
In my application I am using 3.3vfor micro controller (DGND1), 5V for digital (DGND) & analog circuit(AGND), 12V proportional solenoids(12VGND) & 24V for Solenoids(24VGND)
I am getting these voltage from 5V, 12V, 24V SMPS
My doubt is how to connect all these ground points in the circuit.

Regards
Chandu

Click to expand...

This can be quite a sticky problem in reality. The usefulness of using 'star common grounding' is that current flowing in one circuit should not be felt in another circuit, but in reality it can still be a problem. This is usually a larger buss bar where all the common connections are made. The analog circuits are probably the most susitable to common ground bounce problems. Lots of filtering and bypass caps can help.

Lefty

Grounds.

Thanks for the reply

In my circuits I made 3.3V, 5V, 12V, 24V ground lines separately
I am planning to connect all separate grounds with main ground using 600 Ohms, 1500mA Ferrite Bead Chips to avoid the back flow current from other circuits. Here I have 5,12,24V power supplys, shall I connect all these Power supply grounds at single point, shall I call it as main ground.

Please provide some information or circuits related to mixed signal grounds.

Regards
Chandu