// model of comparator with continous transfer function

module continous_comparator(in,ref,out)
 input in,ref;
 output out;
 voltage in,ref,out;
 parameter real output_high = 5;
 parameter real output_low = 0 from (-inf:output_high);
 parameter real slope = 1k from (0:inf);

 real high_minus_low,high_plus_low,vout;

 analog
   begin
     if (analysis("static"))
     begin
       @(initial_step)
       begin
         high_minus_low = 0.5*(output_high - output_low);
         high_plus_low  = 0.5*(output_high + output_low);
       end
     end
     V(out) <+ high_minus_low * tanh(slope*V(in,ref)) + high_plus_low;
   end
endmodule