-------------------------------------------------------------------------------
-- Copyright (c) 2001 Mentor Graphics Corporation
--
-- This model is a component of the Mentor Graphics VHDL-AMS educational open 
-- source model library, and is covered by this license agreement. This model,
-- including any updates, modifications, revisions, copies, and documentation 
-- are copyrighted works of Mentor Graphics. USE OF THIS MODEL INDICATES YOUR 
-- COMPLETE AND UNCONDITIONAL ACCEPTANCE OF THE TERMS AND CONDITIONS SET FORTH
-- IN THIS LICENSE AGREEMENT.  Mentor Graphics grants you a non-exclusive 
-- license to use, reproduce, modify and distribute this model, provided that:
-- (a) no fee or other consideration is charged for any distribution except 
-- compilations distributed in accordance with Section (d) of this license 
-- agreement; (b) the comment text embedded in this model is included verbatim
-- in each copy of this model made or distributed by you, whether or not such 
-- version is modified; (c) any modified version must include a conspicuous 
-- notice that this model has been modified and the date of modification; and 
-- (d) any compilations sold by you that include this model must include a 
-- conspicuous notice that this model is available from Mentor Graphics in its
-- original form at no charge.
--
-- THIS MODEL IS LICENSED TO YOU "AS IS" AND WITH NO WARRANTIES, EXPRESS OR 
-- IMPLIED.  MENTOR GRAPHICS SPECIFICALLY DISCLAIMS ALL IMPLIED WARRANTIES OF 
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-- HAVE NO RESPONSIBILITY FOR ANY DAMAGES WHATSOEVER.
-------------------------------------------------------------------------------
-- File       : comparator_d.vhd
-- Author     : Mentor Graphics
-- Created    : 2001/08/03
-- Last update: 2003-05-13
-------------------------------------------------------------------------------
-- Description: Voltage comparator with digital output
-------------------------------------------------------------------------------
-- Revisions  :
-- Date        Version     Author              Description
-- 2001/08/03  1.0         Mentor Graphics     Created    
-------------------------------------------------------------------------------

-- Use IEEE natures and packages
library IEEE;
use ieee.std_logic_1164.all;
use IEEE.ELECTRICAL_SYSTEMS.all;

entity comparator_d is

  port (
    terminal in_pos : electrical;
    terminal in_neg : electrical;
    signal output : out std_logic := '1'      -- Digital output
    );

end comparator_d;
-------------------------------------------------------------------------------
-- Behavioral architecture
-------------------------------------------------------------------------------
architecture behavioral of comparator_d is
  quantity Vin across in_pos;
  quantity Vref across in_neg;

begin  -- behavioral

  -- purpose: Detect threshold crossing and assign event on output
  -- type   : combinational
  -- inputs : vin'above(thres)
  -- outputs: pulse_signal  
  process (Vin'above(Vref)) is
  begin  -- PROCESS
    if Vin'above(Vref) then
      output <= '1' after 1us;
    else
      output <= '0' after 1us;
    end if;
  end process;

end behavioral;

-------------------------------------------------------------------------------
-- Copyright (c) 2001 Mentor Graphics Corporation
-------------------------------------------------------------------------------