No announcement yet.

LOW noise amplifier power supply requirments.

  • Filter
  • Time
  • Show
Clear All
new posts

  • LOW noise amplifier power supply requirments.

    Dear friends,

    I am trying to design a power supply for this LOW NOISE AMPLIFIER. Everyone is saying that this LNA requires a separate power supply that is not connected to any other load but this LNA.
    This is my LNA:

    Do you have actual numbers, reference design or any other document that discusses this issue?

    Thank you.

  • #2
    Any switching device will draw varying currents from a power supply. That in turn will be seen as noise in the output. The amount that gets to the output is defined by the PSRR.
    Now you add a dedicated power supply for this LNA, but if it bad in noise, it will be no better than sharing it with other devices.

    Best to read and watch a lot of Steve Sandler documents on power supplies. Low noise power supplies and flat impedance.


    • #3
      In these cases I normally use a small LDO to power critical analogue chip / component. But, I am not an expert for sensitive or analogue circuits.


      • #4
        Thank you friends. I think I will use Robert's advice.