driving a transformer with a micro

Discussion in 'General Electronics Chat' started by arudzki, Jul 3, 2012.

  1. arudzki

    Thread Starter New Member

    Sep 25, 2011
    Hello all.

    I'm wondering if it is possible to use a micro to drive a transformer to couple pulsed data across it? If the transformer was center tapped (on the primary side) and the center tap was pulled to some voltage, say 8V through a resistor, and the micro was turning on 2 NPNs (connected to each end of the primary) alternately... so one end would be on, then the other end, at some rate (say 20 Hz, which would indicate a '1').

    Would this work? I'm pretty sure it would, but what would the pitfalls be?

  2. Sensacell

    Well-Known Member

    Jun 19, 2012
    You will need to watch out for core saturation, make sure the flux can reset by way of drive symmetry.
  3. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    Most micro pins will drive 20mA safely, so you could put the transformer primary between 2 micro pins and add a series resistor so current is 20mA max. Then drive the pins differentially to make AC on the transformer primary.

    A small transformer like an audio coupling transformer or telecoms transformer would probably work ok driven with 5v or 20mA.