Impedance Matching with an unknown load

Discussion in 'Homework Help' started by Pheezy, Aug 11, 2014.

  1. Pheezy

    Thread Starter New Member

    May 16, 2014

    1) I somewhat know the answer to this question but just want to clarify. In order to design the impedance matching, I will need to know the load impedance and the source impedance to begin with. Correct?

    2) Let's say I have a circuit designed which is the "load" circuit of my setup. How would I go about measuring its input impedance since this is what is necessary to design the impedance matching circuit?

    3) I would also like to know of any easy to obtain software that may be useful for impedance matching. I am presently trying to get my hands on ADS from my university but if there are any other software which are helpful that you know off, that would be great.

  2. crutschow


    Mar 14, 2008
    Yes, you need to know the source and load impedance for impedance matching.
    A network analyzer can measure impedance.
    What type of circuits are you trying to match?
  3. tome10

    New Member

    Aug 10, 2014
    I think my problem lies in the same arena as your question. I have two LED Circuits with different Resistance. One LED Circuit (Circuit 1) will not work while the other one (Circuit 2) is fine, adding Resistance to the other Circuit seems to balance the load, but I seem to lose light by the resistance level that achieved balance. And also, what are Diodes used for in connecting LED Lighting Strips in a Circuit, like we're trying to block the flow of energy in the wrong direction.
  4. Ramussons

    Active Member

    May 3, 2013
    Circuit 1 where ?
    Circuit 2 Where ?

  5. MikeML

    AAC Fanatic!

    Oct 2, 2009
    Also, balancing LED currents is not anything like impedance matching to accomplish maximum power transfer, usually in AC or RF circuits...
  6. studiot

    AAC Fanatic!

    Nov 9, 2007
    Did someone say these were university questions?
  7. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
    Answer 1: Yes

    Answer 2: Depending on the frequency you're looking at, and your finances, you can measure the impedance with anything from a Vector Network Analyzer to a cheap noise bridge.

    Answer 3: The ARRL Handbook has tons of great information on this, including some Pi-network design software for high power amplifiers.