/* * stripline.cpp - stripline class definition * * Copyright (C) 2011 Michael Margraf * Modifications 2018 for Kicad: Jean-Pierre Charras * * This program 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. * * This program 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 this package; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, * Boston, MA 02110-1301, USA. * */ #include #include #include #include #include #include STRIPLINE::STRIPLINE() : TRANSLINE() { m_Name = "StripLine"; Init(); } // ------------------------------------------------------------------- // calculate characteristic impedance and conductor loss double STRIPLINE::lineImpedance( double height, double& ac ) { double ZL; double hmt = height - m_parameters[T_PRM]; ac = sqrt( m_parameters[FREQUENCY_PRM] / m_parameters[SIGMA_PRM] / 17.2 ); if( m_parameters[PHYS_WIDTH_PRM] / hmt >= 0.35 ) { ZL = m_parameters[PHYS_WIDTH_PRM] + ( 2.0 * height * log( ( 2.0 * height - m_parameters[T_PRM] ) / hmt ) - m_parameters[T_PRM] * log( height * height / hmt / hmt - 1.0 ) ) / M_PI; ZL = ZF0 * hmt / sqrt( m_parameters[EPSILONR_PRM] ) / 4.0 / ZL; ac *= 2.02e-6 * m_parameters[EPSILONR_PRM] * ZL / hmt; ac *= 1.0 + 2.0 * m_parameters[PHYS_WIDTH_PRM] / hmt + ( height + m_parameters[T_PRM] ) / hmt / M_PI * log( 2.0 * height / m_parameters[T_PRM] - 1.0 ); } else { double tdw = m_parameters[T_PRM] / m_parameters[PHYS_WIDTH_PRM]; if( m_parameters[T_PRM] / m_parameters[PHYS_WIDTH_PRM] > 1.0 ) tdw = m_parameters[PHYS_WIDTH_PRM] / m_parameters[T_PRM]; double de = 1.0 + tdw / M_PI * ( 1.0 + log( 4.0 * M_PI / tdw ) ) + 0.236 * pow( tdw, 1.65 ); if( m_parameters[T_PRM] / m_parameters[PHYS_WIDTH_PRM] > 1.0 ) de *= m_parameters[T_PRM] / 2.0; else de *= m_parameters[PHYS_WIDTH_PRM] / 2.0; ZL = ZF0 / 2.0 / M_PI / sqrt( m_parameters[EPSILONR_PRM] ) * log( 4.0 * height / M_PI / de ); ac *= 0.01141 / ZL / de; ac *= de / height + 0.5 + tdw / 2.0 / M_PI + 0.5 / M_PI * log( 4.0 * M_PI / tdw ) + 0.1947 * pow( tdw, 0.65 ) - 0.0767 * pow( tdw, 1.65 ); } return ZL; } // ------------------------------------------------------------------- void STRIPLINE::calcAnalyze() { m_parameters[SKIN_DEPTH_PRM] = skin_depth(); m_parameters[EPSILON_EFF_PRM] = m_parameters[EPSILONR_PRM]; // no dispersion double ac1, ac2; double t = m_parameters[T_PRM]; double a = m_parameters[STRIPLINE_A_PRM]; double h = m_parameters[H_PRM]; m_parameters[Z0_PRM] = 2.0 / ( 1.0 / lineImpedance( 2.0 * a + t, ac1 ) + 1.0 / lineImpedance( 2.0 * ( h - a ) - t, ac2 ) ); m_parameters[LOSS_CONDUCTOR_PRM] = m_parameters[PHYS_LEN_PRM] * 0.5 * ( ac1 + ac2 ); m_parameters[LOSS_DIELECTRIC_PRM] = 20.0 / log( 10.0 ) * m_parameters[PHYS_LEN_PRM] * ( M_PI / C0 ) * m_parameters[FREQUENCY_PRM] * sqrt( m_parameters[EPSILONR_PRM] ) * m_parameters[TAND_PRM]; m_parameters[ANG_L_PRM] = 2.0 * M_PI * m_parameters[PHYS_LEN_PRM] * sqrt( m_parameters[EPSILONR_PRM] ) * m_parameters[FREQUENCY_PRM] / C0; // in radians } void STRIPLINE::showAnalyze() { setProperty( Z0_PRM, m_parameters[Z0_PRM] ); setProperty( ANG_L_PRM, m_parameters[ANG_L_PRM] ); if( !std::isfinite( m_parameters[Z0_PRM] ) || m_parameters[Z0_PRM] < 0 ) { setErrorLevel( Z0_PRM, TRANSLINE_ERROR ); } if( !std::isfinite( m_parameters[ANG_L_PRM] ) || m_parameters[ANG_L_PRM] < 0 ) { setErrorLevel( ANG_L_PRM, TRANSLINE_ERROR ); } if( !std::isfinite( m_parameters[PHYS_LEN_PRM] ) || m_parameters[PHYS_LEN_PRM] < 0 ) { setErrorLevel( PHYS_LEN_PRM, TRANSLINE_WARNING ); } if( !std::isfinite( m_parameters[PHYS_WIDTH_PRM] ) || m_parameters[PHYS_WIDTH_PRM] < 0 ) { setErrorLevel( PHYS_WIDTH_PRM, TRANSLINE_WARNING ); } if( m_parameters[STRIPLINE_A_PRM] + m_parameters[T_PRM] >= m_parameters[H_PRM] ) { setErrorLevel( STRIPLINE_A_PRM, TRANSLINE_WARNING ); setErrorLevel( T_PRM, TRANSLINE_WARNING ); setErrorLevel( H_PRM, TRANSLINE_WARNING ); setErrorLevel( Z0_PRM, TRANSLINE_ERROR ); } } void STRIPLINE::showSynthesize() { setProperty( PHYS_LEN_PRM, m_parameters[PHYS_LEN_PRM] ); setProperty( PHYS_WIDTH_PRM, m_parameters[PHYS_WIDTH_PRM] ); if( !std::isfinite( m_parameters[PHYS_LEN_PRM] ) || m_parameters[PHYS_LEN_PRM] < 0 ) { setErrorLevel( PHYS_LEN_PRM, TRANSLINE_ERROR ); } if( !std::isfinite( m_parameters[PHYS_WIDTH_PRM] ) || m_parameters[PHYS_WIDTH_PRM] < 0 ) { setErrorLevel( PHYS_WIDTH_PRM, TRANSLINE_ERROR ); } if( !std::isfinite( m_parameters[Z0_PRM] ) || m_parameters[Z0_PRM] < 0 ) { setErrorLevel( Z0_PRM, TRANSLINE_WARNING ); } if( !std::isfinite( m_parameters[ANG_L_PRM] ) || m_parameters[ANG_L_PRM] < 0 ) { setErrorLevel( ANG_L_PRM, TRANSLINE_WARNING ); } if( m_parameters[STRIPLINE_A_PRM] + m_parameters[T_PRM] >= m_parameters[H_PRM] ) { setErrorLevel( STRIPLINE_A_PRM, TRANSLINE_WARNING ); setErrorLevel( T_PRM, TRANSLINE_WARNING ); setErrorLevel( H_PRM, TRANSLINE_WARNING ); setErrorLevel( PHYS_WIDTH_PRM, TRANSLINE_ERROR ); } } // ------------------------------------------------------------------- void STRIPLINE::show_results() { setResult( 0, m_parameters[EPSILON_EFF_PRM], "" ); setResult( 1, m_parameters[LOSS_CONDUCTOR_PRM], "dB" ); setResult( 2, m_parameters[LOSS_DIELECTRIC_PRM], "dB" ); setResult( 3, m_parameters[SKIN_DEPTH_PRM] / UNIT_MICRON, "µm" ); } #define MAX_ERROR 0.000001 // ------------------------------------------------------------------- void STRIPLINE::calcSynthesize() { minimizeZ0Error1D( &( m_parameters[PHYS_WIDTH_PRM] ) ); }