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-- Copyright (C) 2002 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the
-- Free Software Foundation; either version 2 of the License, or (at
-- your option) any later version.
-- VESTs is distributed in the hope that it will be useful, but WITHOUT
-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
-- FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
-- for more details.
-- You should have received a copy of the GNU General Public License
-- along with VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
library ieee_proposed; use ieee_proposed.electrical_systems.all;
entity opamp is
port ( terminal positive_supply, negative_supply : electrical;
terminal plus_in, minus_in, output : electrical );
end entity opamp;
----------------------------------------------------------------
architecture saturating of opamp is
constant gain : real := 50.0;
quantity v_pos across positive_supply;
quantity v_neg across negative_supply;
quantity v_in across plus_in to minus_in;
quantity v_out across i_out through output;
quantity v_amplified : voltage;
begin
if v_in'above(v_pos / gain) use
v_amplified == v_pos;
elsif not v_in'above(v_neg / gain) use
v_amplified == v_neg;
else
v_amplified == gain * v_in;
end use;
break on v_in'above(v_pos/gain), v_in'above(v_neg/gain);
v_out == v_amplified'slew(1.0e6,-1.0e6);
end architecture saturating;
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