-------------------------------------------------------------------------------
-- Lead-Lag Filter
--
--  Transfer Function:
--
--                  (s + w1)         
--    H(s) =  k *  ----------
--                  (s + w2)
--
-- DC Gain = k*w1/w2
-------------------------------------------------------------------------------

-- Use IEEE_proposed instead of disciplines
library IEEE;
use IEEE.electrical_systems.all;
library IEEE;
use ieee.math_real.all;

entity lead_lag_e is
	generic (
		k: real := 1.0;  			-- Gain multiplier
		f1: real := 10.0;			-- First break frequency (zero)
		f2: real := 100.0);		-- Second break frequency (pole)
	port 	(	terminal input: electrical;
			terminal output: electrical);
end entity lead_lag_e;

architecture simple of lead_lag_e is
  QUANTITY vin ACROSS input TO ELECTRICAL_REF;
  QUANTITY vout ACROSS iout THROUGH output TO ELECTRICAL_REF;

	quantity vin_temp : real;
	constant w1 : real := f1*math_2_pi;
	constant w2 : real := f2*math_2_pi;
	constant num : real_vector := (w1, 1.0);                                                    
	constant den : real_vector := (w2, 1.0);
begin
	vin_temp == vin;
	vout == k*vin_temp'ltf(num, den);
end architecture simple;