Understanding Datasheet....

Discussion in 'General Electronics Chat' started by Gibson486, May 27, 2014.

  1. Gibson486

    Thread Starter Member

    Jul 20, 2012
    199
    12
    I want to fully understand the following datasheet.....

    http://www.tamuracorp.com/clientuploads/pdfs/engineeringdocs/MET-23.pdf

    I am trying to get an output wave close to its dielectric strength.

    1. Primary Source Impedance. It is the impedance in the primary. Does the CT stand for coil turns? If so, doesn't that go against the definition? If they give you the ration in terms of impedance, then you have to take the square root to get the turn ratio. Is that not correct.

    2. Sec. Impedance. Same question as 1.

    3. Primary DC current....this is the max current it can take on DC on the primary, but what about AC?

    4. Operating Level...This is the max power it can handle on the output?

    5. Frequency Response....what does it mean relative to 1kHz? Also, 3dB spans a long way. What happens if I go over that frequency.

    6. Longitudinal Balance...this measures how well it can transport over a cable? What happens if I go over 1Khz?

    On the top it says 65mW max in secondary and reflect a primary source impedance of 1.6kCT with a 3.2 ohm load on the secondary.

    A few questions with this...

    It reflects a primary source impedance with that known load... Does that mean the driver sees that reflection? If I did want to put a cable...I would most definitely have to impedance match, correct? Which impedance do I use? The side the connects to the cable, or the side the driver sees?

    To make more voltage, I would have to put this backwards. Do all these specs go out the window?
     
  2. Papabravo

    Expert

    Feb 24, 2006
    10,143
    1,790
    CT stands for "center tapped". A center tapped winging has a termination in the center and you can think of it as two inductors in series.
     
  3. Gibson486

    Thread Starter Member

    Jul 20, 2012
    199
    12
    Does that mean it is 3.2K total if I do not use the center tap?
     
  4. AnalogKid

    Distinguished Member

    Aug 1, 2013
    4,538
    1,251
    The impedance for the total primary (when the secondary is loaded as indicated) is 1.6K ohms. The impedance of each half of the primary is 400 ohms. This is because the impedance is proportional th the square of the number of turns of wire. 1/2 the turns (squared) ==> 1/4 the impedance.

    What you have here is a low power (65 mW) output transformer designed for a 3.2 Ohm speaker. Note that the low frequency response isn't very good but the high end is exceptional. Both of these specs are due to the very small core size. I have used similar xfmrs in the past, and they work fine for voice as long as you don't expect recording studio sound.

    ak
     
  5. Gibson486

    Thread Starter Member

    Jul 20, 2012
    199
    12
    So, what if I turn it around and make the secondary the primary and vice versa?

    Also, when I see transformers, I usually see diodes. Wouldn't a diode clip the wave of an AC signal?
     
    Last edited: May 28, 2014
  6. AnalogKid

    Distinguished Member

    Aug 1, 2013
    4,538
    1,251
    Yes, you can flip it around. Transformers are bidirectional, although some characteristics like frequency response might change.

    When you usually see diodes, that usually means it's a power transformer in a power supply. But many transformers have other uses, such as coupling Ethernet signals onto CAT-5 cable, or RF into an antenna, or...audio.

    ak
     
Loading...