What is a star ground system?

Discussion in 'General Electronics Chat' started by Fobio Design, Jun 2, 2016.

  1. Fobio Design

    Thread Starter New Member

    May 11, 2016

    Hope you are all having a good day so far. I have a question regarding star ground systems. What is a star ground system? What are the benefits of this system? And how does one go about integrating a star ground system into their circuit? I have attached the schematics of my project.

    Thanks for reading and I appreciate the help!
  2. ISB123

    Well-Known Member

    May 21, 2014
    Its when all ground connections go to a single point.
    Fobio Design likes this.
  3. WBahn


    Mar 31, 2012
    Basically you run all of your ground (or common) connections back to a single point that then has a very low impedance route back to the source. You often do the same with the power side. The details vary a bit depending on if you are talking about power systems versus something like an analog circuit, but the general idea is the same.

    A big advantage, particularly for analog systems, is that the noise associated with the current draw (and variations in the current draw) of one portion of the circuit have a significantly smaller impact on other circuits.
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  4. BR-549

    Distinguished Member

    Sep 22, 2013
    The whole purpose of a star ground is to keep all circuit grounds at the same potential.
    This is accomplished by making sure the ground conductors are the same length.
  5. Lestraveled

    Well-Known Member

    May 19, 2014
    Wrong. It is to minimize one "leg" effecting another "leg". In other words, a star system minimizes voltage transients, generated by one section, from propagating through out the rest of the circuit.
  6. MaxHeadRoom


    Jul 18, 2013
    IOW to prevent ground loops.
    Which also ties in with equi-potential bonding, which mainly applies to electronically controlled machinery and control enclosures.
  7. crutschow


    Mar 14, 2008
    An example: Suppose you have a preamp with a high gain driving a power output stage delivering a high current to the load.
    If you connect the output load common to a ground line that also is the preamp ground, then the high currents will cause a small voltage drop in the ground resistance at the preamp which will (usually) adversely affect the preamp operation.
    Thus you want the preamp ground to have a ground return to the power supply separate from the output stage ground.
    The power supply becomes the single point (star) ground point.
    Lestraveled likes this.