Low Impedance Ground [hlp]

[elf61]

hi - what is the LOW IMPEDANCE GROUND?

 

[House_Cat]

In the simplest terms:

Impedance is the resistance to alternating current (AC) flow in a circuit. "Low impedance ground" is telling you that you need a return path that has the least amount of resistance to AC possible.

An example would be a low impedance ground connection made through a short fat wire instead of a longer thinner wire. Or a ground connection made to a dedicated ground rod instead of through water pipes.

On a printed circuit board a low impedance ground connection would be one made directly to a ground plane instead of through a trace. Or a ground connection made through several vias instead of just one.

If your question is about a specific circuit, it would help if you could post some details. A more detailed and precise answer would then be possible.

 

[sumiii]

In the simplest terms:

If your question is about a specific circuit, it would help if you could post some details. A more detailed and precise answer would then be possible.

I am using a RS-485 Network in my circuit with ST485 ECDR IC.My circuit suddenly stop working,Stop means that during working slave stop to reply the master,then when I replace the IC it start to replay again.Transceiver was damaged .

This behaviour is very random,sometime it occur with in a hour and sometime it occur after months.

When first time the problem occur in my slave device, I checked on oscilloscope and found that there was some noise from ground, so I separate the ground of Master and slave device and then it start working fine.
After some months this problem again occur and this time failure ratio was much greater, so I thought without a common ground, the circuit may work, but the energy from the imbalance has to go somewhere and may dissipate as electromagnetic radiation.
So I decided to do these 2 things
1- Addition of TVS.
2-The RS-485 specification recommends connecting a 100-W resistor of at least 0.5 W in series between each node’s signal ground and the network’s ground wire, as attached Figure shows. This way, if the ground potentials of two nodes vary, the resistors limit the current in the ground wire.

Please suggest me if there is any better solution