Transformer:

--------------------------------------------------------------------------
   An ideal transformer.  

   The current ratio can be n or 1/n where n is the ratio of turns in the
   two inductors.

--------------------------------------------------------------------------
   Form:
   [v2, i2] = Transformer( v1, i1, a )
--------------------------------------------------------------------------

   ------
   Inputs
   ------
   v1           (1,1) Input voltage
   i1           (1,1) Input current
   a            (1,1) Current ratio

   -------
   Outputs
   -------
   v2           (1,1) Output voltage
   i2           (1,1) Output current

--------------------------------------------------------------------------
	References:	  http://electronicdesign.com/Files/29/6204/Figure_02.gif
--------------------------------------------------------------------------