// Copyright(c) 2009-2014 Accellera Systems Initiative Inc.
// 1370 Trancas Street #163, Napa, CA 94558, USA.
//
// The material in constants.vams is an essential part of the Accellera Systems
// Initiative ("Accellera") Verilog-AMS Language Standard. Verbatim copies of
// the material in this Annex may be used and distributed without restriction.
// All other uses require permission from Accellera IP Committee
// (ipr-chair@lists.accellera.org).
// All other rights reserved
//
// Version 2.4.0
//

// Mathematical and physical constants
`ifdef CONSTANTS_VAMS
`else
`define CONSTANTS_VAMS 1

// M_ is a mathematical constant
`define    M_E                2.7182818284590452354
`define    M_LOG2E            1.4426950408889634074
`define    M_LOG10E           0.43429448190325182765
`define    M_LN2              0.69314718055994530942
`define    M_LN10             2.30258509299404568402
`define    M_PI               3.14159265358979323846
`define    M_TWO_PI           6.28318530717958647693
`define    M_PI_2             1.57079632679489661923
`define    M_PI_4             0.78539816339744830962
`define    M_1_PI             0.31830988618379067154
`define    M_2_PI             0.63661977236758134308
`define    M_2_SQRTPI         1.12837916709551257390
`define    M_SQRT2            1.41421356237309504880
`define    M_SQRT1_2          0.70710678118654752440

// The following constants have been taken from http://physics.nist.gov
// P_ is a physical constant
// charge of electron in Coulombs 
`define    P_Q_SPICE          1.60219e-19
`define    P_Q_OLD            1.6021918e-19
`define    P_Q_NIST1998       1.602176462e-19
`define    P_Q_NIST2010       1.602176565e-19
// speed of light in vacuum in meters/second
`define    P_C                2.99792458e8
// Boltzmann's constant in Joules/Kelvin
`define    P_K_SPICE          1.38062e-23
`define    P_K_OLD            1.3806226e-23
`define    P_K_NIST1998       1.3806503e-23
`define    P_K_NIST2010       1.3806488e-23
// Planck's constant in Joules*second
`define    P_H_SPICE          6.62620e-34
`define    P_H_OLD            6.6260755e-34
`define    P_H_NIST1998       6.62606876e-34
`define    P_H_NIST2010       6.62606957e-34
// permittivity of vacuum in Farads/meter
`define    P_EPS0_SPICE       8.854214871e-12
`define    P_EPS0_OLD         8.85418792394420013968e-12
`define    P_EPS0_NIST1998    8.854187817e-12
`define    P_EPS0_NIST2010    8.854187817e-12
// permeability of vacuum in Henrys/meter
`define    P_U0               (4.0e-7 * `M_PI)
// zero Celsius in Kelvin
`define    P_CELSIUS0         273.15

`ifdef PHYSICAL_CONSTANTS_SPICE
// from UC Berkeley SPICE 3F5
`define    P_Q                `P_Q_SPICE
`define    P_K                `P_K_SPICE
`define    P_H                `P_H_SPICE
`define    P_EPS0             `P_EPS0_SPICE

`else
`ifdef PHYSICAL_CONSTANTS_OLD
// from Verilog-A LRM 1.0 and Verilog-AMS LRM 2.0
`define    P_Q                `P_Q_OLD
`define    P_K                `P_K_OLD
`define    P_H                `P_H_OLD
`define    P_EPS0             `P_EPS0_OLD

`else
`ifdef PHYSICAL_CONSTANTS_NIST2010
`define    P_Q                `P_Q_NIST2010
`define    P_K                `P_K_NIST2010
`define    P_H                `P_H_NIST2010
`define    P_EPS0             `P_EPS0_NIST2010

`else
// use NIST1998 values as in LRM 2.2 - 2.3 for backwards-compatibility
`define    P_Q                `P_Q_NIST1998
`define    P_K                `P_K_NIST1998
`define    P_H                `P_H_NIST1998
`define    P_EPS0             `P_EPS0_NIST1998
`endif
`endif
`endif

`endif
