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common/transline_calculations/stripline.cpp
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1/*
2 * Copyright (C) 2001 Gopal Narayanan <[email protected]>
3 * Copyright (C) 2002 Claudio Girardi <[email protected]>
4 * Copyright (C) 2005, 2006 Stefan Jahn <[email protected]>
5 * Modified for Kicad: 2018 Jean-Pierre Charras <jp.charras at wanadoo.fr>
6 * Copyright The KiCad Developers, see AUTHORS.txt for contributors.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2
11 * of the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this package; see the file COPYING. If not, write to
20 * the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
21 * Boston, MA 02110-1301, USA.
22 */
23
24#include <transline_calculations/stripline.h>
25#include <transline_calculations/units.h>
26
27
28namespace TC = TRANSLINE_CALCULATIONS;
29using TCP = TRANSLINE_PARAMETERS;
30
31
32void STRIPLINE::Analyse()
33{
34 SetParameter( TCP::SKIN_DEPTH, SkinDepth() );
35 SetParameter( TCP::EPSILON_EFF, GetParameter( TCP::EPSILONR ) ); // no dispersion
36
37 double ac1, ac2;
38 double t = GetParameter( TCP::T );
39 double a = GetParameter( TCP::STRIPLINE_A );
40 double h = GetParameter( TCP::H );
41 SetParameter( TCP::Z0,
42 2.0 / ( 1.0 / lineImpedance( 2.0 * a + t, ac1 ) + 1.0 / lineImpedance( 2.0 * ( h - a ) - t, ac2 ) ) );
43 SetParameter( TCP::LOSS_CONDUCTOR, GetParameter( TCP::PHYS_LEN ) * ( ac1 + ac2 ) );
44 SetParameter( TCP::LOSS_DIELECTRIC, TC::LOG2DB * GetParameter( TCP::PHYS_LEN ) * ( M_PI / TC::C0 )
45 * GetParameter( TCP::FREQUENCY ) * sqrt( GetParameter( TCP::EPSILONR ) )
46 * GetParameter( TCP::TAND ) );
47
48 SetParameter( TCP::ANG_L, 2.0 * M_PI * GetParameter( TCP::PHYS_LEN ) * sqrt( GetParameter( TCP::EPSILONR ) )
49 * GetParameter( TCP::FREQUENCY ) / TC::C0 ); // in radians
50
51 unit_prop_delay = UnitPropagationDelay( GetParameter( TCP::EPSILON_EFF ) );
52}
53
54
55bool STRIPLINE::Synthesize( const SYNTHESIZE_OPTS aOpts )
56{
57 return MinimiseZ0Error1D( TCP::PHYS_WIDTH, TCP::Z0 );
58}
59
60
61void STRIPLINE::SetAnalysisResults()
62{
63 SetAnalysisResult( TCP::EPSILON_EFF, GetParameter( TCP::EPSILON_EFF ) );
64 SetAnalysisResult( TCP::UNIT_PROP_DELAY, unit_prop_delay );
65 SetAnalysisResult( TCP::LOSS_CONDUCTOR, GetParameter( TCP::LOSS_CONDUCTOR ) );
66 SetAnalysisResult( TCP::LOSS_DIELECTRIC, GetParameter( TCP::LOSS_DIELECTRIC ) );
67 SetAnalysisResult( TCP::SKIN_DEPTH, GetParameter( TCP::SKIN_DEPTH ) );
68
69 const double Z0 = GetParameter( TCP::Z0 );
70 const double ANG_L = GetParameter( TCP::ANG_L );
71 const double L = GetParameter( TCP::PHYS_LEN );
72 const double W = GetParameter( TCP::PHYS_WIDTH );
73
74 const bool Z0_invalid = !std::isfinite( Z0 ) || Z0 < 0;
75 const bool ANG_L_invalid = !std::isfinite( ANG_L ) || ANG_L < 0;
76 const bool L_invalid = !std::isfinite( L ) || L < 0;
77 const bool W_invalid = !std::isfinite( W ) || W <= 0;
78
79 bool invalid = false;
80
81 if( GetParameter( TCP::STRIPLINE_A ) + GetParameter( TCP::T ) >= GetParameter( TCP::H ) )
82 invalid = true;
83
84 SetAnalysisResult( TCP::Z0, Z0, Z0_invalid || invalid ? TRANSLINE_STATUS::TS_ERROR : TRANSLINE_STATUS::OK );
85 SetAnalysisResult( TCP::ANG_L, ANG_L, ANG_L_invalid ? TRANSLINE_STATUS::TS_ERROR : TRANSLINE_STATUS::OK );
86 SetAnalysisResult( TCP::PHYS_LEN, L, L_invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
87 SetAnalysisResult( TCP::PHYS_WIDTH, W, W_invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
88 SetAnalysisResult( TCP::STRIPLINE_A, GetParameter( TCP::STRIPLINE_A ),
89 invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
90 SetAnalysisResult( TCP::T, GetParameter( TCP::T ), invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
91 SetAnalysisResult( TCP::H, GetParameter( TCP::H ), invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
92 SetAnalysisResult( TCP::Z0, GetParameter( TCP::Z0 ), invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
93}
94
95
96void STRIPLINE::SetSynthesisResults()
97{
98 SetSynthesisResult( TCP::EPSILON_EFF, GetParameter( TCP::EPSILON_EFF ) );
99 SetSynthesisResult( TCP::UNIT_PROP_DELAY, unit_prop_delay );
100 SetSynthesisResult( TCP::LOSS_CONDUCTOR, GetParameter( TCP::LOSS_CONDUCTOR ) );
101 SetSynthesisResult( TCP::LOSS_DIELECTRIC, GetParameter( TCP::LOSS_DIELECTRIC ) );
102 SetSynthesisResult( TCP::SKIN_DEPTH, GetParameter( TCP::SKIN_DEPTH ) );
103
104 const double Z0 = GetParameter( TCP::Z0 );
105 const double ANG_L = GetParameter( TCP::ANG_L );
106 const double L = GetParameter( TCP::PHYS_LEN );
107 const double W = GetParameter( TCP::PHYS_WIDTH );
108
109 const bool Z0_invalid = !std::isfinite( Z0 ) || Z0 < 0;
110 const bool ANG_L_invalid = !std::isfinite( ANG_L ) || ANG_L < 0;
111 const bool L_invalid = !std::isfinite( L ) || L < 0;
112 const bool W_invalid = !std::isfinite( W ) || W <= 0;
113
114 bool invalid = false;
115
116 if( GetParameter( TCP::STRIPLINE_A ) + GetParameter( TCP::T ) >= GetParameter( TCP::H ) )
117 invalid = true;
118
119 SetSynthesisResult( TCP::Z0, Z0, Z0_invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
120 SetSynthesisResult( TCP::ANG_L, ANG_L, ANG_L_invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
121 SetSynthesisResult( TCP::PHYS_LEN, L, L_invalid ? TRANSLINE_STATUS::TS_ERROR : TRANSLINE_STATUS::OK );
122 SetSynthesisResult( TCP::PHYS_WIDTH, W, W_invalid || invalid ? TRANSLINE_STATUS::TS_ERROR : TRANSLINE_STATUS::OK );
123 SetSynthesisResult( TCP::STRIPLINE_A, GetParameter( TCP::STRIPLINE_A ),
124 invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
125 SetSynthesisResult( TCP::T, GetParameter( TCP::T ), invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
126 SetSynthesisResult( TCP::H, GetParameter( TCP::H ), invalid ? TRANSLINE_STATUS::WARNING : TRANSLINE_STATUS::OK );
127}
128
129
130double STRIPLINE::lineImpedance( double aHeight, double& aAc ) const
131{
132 double ZL;
133 const double hmt = aHeight - GetParameter( TCP::T );
134
135 aAc = sqrt( GetParameter( TCP::FREQUENCY ) / GetParameter( TCP::SIGMA ) / 17.2 );
136
137 if( GetParameter( TCP::PHYS_WIDTH ) / hmt >= 0.35 )
138 {
139 ZL = GetParameter( TCP::PHYS_WIDTH )
140 + ( 2.0 * aHeight * log( ( 2.0 * aHeight - GetParameter( TCP::T ) ) / hmt )
141 - GetParameter( TCP::T ) * log( aHeight * aHeight / hmt / hmt - 1.0 ) )
142 / M_PI;
143 ZL = TC::ZF0 * hmt / sqrt( GetParameter( TCP::EPSILONR ) ) / 4.0 / ZL;
144
145 aAc *= 2.02e-6 * GetParameter( TCP::EPSILONR ) * ZL / hmt;
146 aAc *= 1.0 + 2.0 * GetParameter( TCP::PHYS_WIDTH ) / hmt
147 + ( aHeight + GetParameter( TCP::T ) ) / hmt / M_PI
148 * log( 2.0 * aHeight / GetParameter( TCP::T ) - 1.0 );
149 }
150 else
151 {
152 double tdw = GetParameter( TCP::T ) / GetParameter( TCP::PHYS_WIDTH );
153
154 if( GetParameter( TCP::T ) / GetParameter( TCP::PHYS_WIDTH ) > 1.0 )
155 tdw = GetParameter( TCP::PHYS_WIDTH ) / GetParameter( TCP::T );
156
157 double de = 1.0 + tdw / M_PI * ( 1.0 + log( 4.0 * M_PI / tdw ) ) + 0.236 * pow( tdw, 1.65 );
158
159 if( GetParameter( TCP::T ) / GetParameter( TCP::PHYS_WIDTH ) > 1.0 )
160 de *= GetParameter( TCP::T ) / 2.0;
161 else
162 de *= GetParameter( TCP::PHYS_WIDTH ) / 2.0;
163
164 ZL = TC::ZF0 / 2.0 / M_PI / sqrt( GetParameter( TCP::EPSILONR ) ) * log( 4.0 * aHeight / M_PI / de );
165
166 aAc *= 0.01141 / ZL / de;
167 aAc *= de / aHeight + 0.5 + tdw / 2.0 / M_PI + 0.5 / M_PI * log( 4.0 * M_PI / tdw ) + 0.1947 * pow( tdw, 0.65 )
168 - 0.0767 * pow( tdw, 1.65 );
169 }
170
171 return ZL;
172}
STRIPLINE::Synthesize
bool Synthesize(SYNTHESIZE_OPTS aOpts) override
Synthesis track geometry parameters to match given Z0.
Definition: common/transline_calculations/stripline.cpp:55
STRIPLINE::SetAnalysisResults
void SetAnalysisResults() override
Sets the output values and status following analysis.
Definition: common/transline_calculations/stripline.cpp:61
STRIPLINE::SetSynthesisResults
void SetSynthesisResults() override
Sets the output values and status following synthesis.
Definition: common/transline_calculations/stripline.cpp:96
STRIPLINE::lineImpedance
double lineImpedance(double aHeight, double &aAc) const
Calculate characteristic impedance and conductor loss (in db/meter)
Definition: common/transline_calculations/stripline.cpp:130
STRIPLINE::Analyse
void Analyse() override
Analyse track geometry parameters to output Z0 and Ang_L.
Definition: common/transline_calculations/stripline.cpp:32
TRANSLINE_CALCULATION_BASE::GetParameter
double GetParameter(const TRANSLINE_PARAMETERS aParam) const
Gets the given calculation property.
Definition: transline_calculation_base.h:121
TRANSLINE_CALCULATION_BASE::SetParameter
void SetParameter(const TRANSLINE_PARAMETERS aParam, const double aValue)
Sets the given calculation property.
Definition: transline_calculation_base.h:118
TRANSLINE_CALCULATION_BASE::SetSynthesisResult
void SetSynthesisResult(TRANSLINE_PARAMETERS aParam, const double aValue, const TRANSLINE_STATUS aStatus=TRANSLINE_STATUS::OK)
Sets a synthesis result.
Definition: transline_calculation_base.cpp:58
TRANSLINE_CALCULATION_BASE::MinimiseZ0Error1D
bool MinimiseZ0Error1D(TRANSLINE_PARAMETERS aOptimise, TRANSLINE_PARAMETERS aMeasure)
minimizeZ0Error1D
Definition: transline_calculation_base.cpp:65
TRANSLINE_CALCULATION_BASE::SkinDepth
double SkinDepth() const
Calculate skin depth.
Definition: transline_calculation_base.cpp:144
TRANSLINE_CALCULATION_BASE::SetAnalysisResult
void SetAnalysisResult(TRANSLINE_PARAMETERS aParam, const double aValue, const TRANSLINE_STATUS aStatus=TRANSLINE_STATUS::OK)
Sets an analysis result.
Definition: transline_calculation_base.cpp:51
TRANSLINE_CALCULATION_BASE::UnitPropagationDelay
static double UnitPropagationDelay(double aEpsilonEff)
Calculates the unit propagation delay (ps/cm) for the given effective permittivity.
Definition: transline_calculation_base.cpp:153
stripline.h
units.h
TRANSLINE_CALCULATIONS
Definition: common/transline_calculations/units.h:60
TRANSLINE_CALCULATIONS::LOG2DB
const double LOG2DB
Definition: common/transline_calculations/units.h:68
TRANSLINE_CALCULATIONS::C0
constexpr double C0
Definition: common/transline_calculations/units.h:63
TRANSLINE_CALCULATIONS::ZF0
constexpr double ZF0
Definition: common/transline_calculations/units.h:64
SYNTHESIZE_OPTS
SYNTHESIZE_OPTS
Options for specifying synthesis inputs, targets, or strategies.
Definition: transline_calculation_base.h:82
TRANSLINE_PARAMETERS
TRANSLINE_PARAMETERS
All possible parameters used (as inputs or outputs) by the transmission line calculations.
Definition: transline_calculation_base.h:30
TRANSLINE_PARAMETERS::Z0
@ Z0
TRANSLINE_PARAMETERS::ANG_L
@ ANG_L