mame/src/lib/netlist/analog/nld_bjt.cpp
2017-03-05 16:19:59 +01:00

438 lines
15 KiB
C++

// license:GPL-2.0+
// copyright-holders:Couriersud
/*
* nld_bjt.c
*
*/
#include "../solver/nld_solver.h"
#include "nlid_twoterm.h"
#include "../nl_setup.h"
#include <cmath>
namespace netlist
{
namespace analog
{
class diode
{
public:
diode() : m_Is(1e-15), m_VT(0.0258), m_VT_inv(1.0 / m_VT) {}
diode(const nl_double Is, const nl_double n)
{
m_Is = Is;
m_VT = 0.0258 * n;
m_VT_inv = 1.0 / m_VT;
}
void set(const nl_double Is, const nl_double n)
{
m_Is = Is;
m_VT = 0.0258 * n;
m_VT_inv = 1.0 / m_VT;
}
nl_double I(const nl_double V) const { return m_Is * std::exp(V * m_VT_inv) - m_Is; }
nl_double g(const nl_double V) const { return m_Is * m_VT_inv * std::exp(V * m_VT_inv); }
nl_double V(const nl_double I) const { return std::log1p(I / m_Is) * m_VT; } // log1p(x)=log(1.0 + x)
nl_double gI(const nl_double I) const { return m_VT_inv * (I + m_Is); }
private:
nl_double m_Is;
nl_double m_VT;
nl_double m_VT_inv;
};
// -----------------------------------------------------------------------------
// nld_Q - Base classes
// -----------------------------------------------------------------------------
/*! Class representing the bjt model paramers.
*
* This is the model representation of the bjt model. Typically, SPICE uses
* the following parameters. A "Y" in the first column indicates that the
* parameter is actually used in netlist.
*
* | NL? | name | parameter | units | default | example | area |
* |:---:|------|-----------------------------------------------------------------------|-------|---------:|----------------:|:----:|
* | Y | IS | transport saturation current | A | 1E-016 | 1E-015 | * |
* | Y | BF | ideal maximum forward beta | - | 100 | 100 | |
* | Y | NF | forward current emission coefficient | - | 1 | 1 | |
* | | VAF | forward Early voltage | V | infinite | 200 | |
* | | IKF | corner for forward beta high current roll-off | A | infinite | 0.01 | * |
* | | ISE | B-E leakage saturation current | A | 0 | 0.0000000000001 | * |
* | | NE | B-E leakage emission coefficient | - | 1.5 | 2 | |
* | Y | BR | ideal maximum reverse beta | - | 1 | 0.1 | |
* | Y | NR | reverse current emission coefficient | - | 1 | 1 | |
* | | VAR | reverse Early voltage | V | infinite | 200 | |
* | | IKR | corner for reverse beta high current roll-off | A | infinite | 0.01 | * |
* | | ISC | leakage saturation current | A | 0 | 8 | |
* | | NC | leakage emission coefficient | - | 2 | 1.5 | |
* | | RB | zero bias base resistance | | 0 | 100 | * |
* | | IRB | current where base resistance falls halfway to its min value | A | infinte | 0.1 | * |
* | | RBM | minimum base resistance at high currents | | RB | 10 | * |
* | | RE | emitter resistance | | 0 | 1 | * |
* | | RC | collector resistance | | 0 | 10 | * |
* | | CJE | B-E zero-bias depletion capacitance | F | 0 | 2pF | * |
* | | VJE | B-E built-in potential | V | 0.75 | 0.6 | |
* | | MJE | B-E junction exponential factor | - | 0.33 | 0.33 | |
* | | TF | ideal forward transit time | sec | 0 | 0.1ns | |
* | | XTF | coefficient for bias dependence of TF | - | 0 | | |
* | | VTF | voltage describing VBC dependence of TF | V | infinite | | |
* | | ITF | high-current parameter for effect on TF | A | 0 | | * |
* | | PTF | excess phase at freq=1.0/(TF*2PI) Hz | deg | 0 | | |
* | | CJC | B-C zero-bias depletion capacitance | F | 0 | 2pF | * |
* | | VJC | B-C built-in potential | V | 0.75 | 0.5 | |
* | | MJC | B-C junction exponential factor | - | 0.33 | 0.5 | |
* | | XCJC | fraction of B-C depletion capacitance connected to internal base node | - | 1 | | |
* | | TR | ideal reverse transit time | sec | 0 | 10ns | |
* | | CJS | zero-bias collector-substrate capacitance | F | 0 | 2pF | * |
* | | VJS | substrate junction built-in potential | V | 0.75 | | |
* | | MJS | substrate junction exponential factor | - | 0 | 0.5 | |
* | | XTB | forward and reverse beta temperature exponent | - | 0 | | |
* | | EG | energy gap for temperature effect on IS | eV | 1.11 | | |
* | | XTI | temperature exponent for effect on IS | - | 3 | | |
* | | KF | flicker-noise coefficient | - | 0 | | |
* | | AF | flicker-noise exponent | - | 1 | | |
* | | FC | coefficient for forward-bias depletion capacitance formula | - | 0.5 | | |
* | | TNOM | Parameter measurement temperature | C | 27 | 50 | | */
class bjt_model_t : public param_model_t
{
public:
bjt_model_t(device_t &device, const pstring &name, const pstring &val)
: param_model_t(device, name, val)
, m_IS(*this, "IS")
, m_BF(*this, "BF")
, m_NF(*this, "NF")
, m_BR(*this, "BR")
, m_NR(*this, "NR")
{}
value_t m_IS; //!< transport saturation current
value_t m_BF; //!< ideal maximum forward beta
value_t m_NF; //!< forward current emission coefficient
value_t m_BR; //!< ideal maximum reverse beta
value_t m_NR; //!< reverse current emission coefficient
};
// Have a common start for transistors
NETLIB_OBJECT(Q)
{
public:
enum q_type {
BJT_NPN,
BJT_PNP
};
NETLIB_CONSTRUCTOR(Q)
, m_model(*this, "MODEL", "NPN")
, m_qtype(BJT_NPN)
{
}
NETLIB_IS_DYNAMIC(true)
//NETLIB_RESETI();
NETLIB_UPDATEI();
inline q_type qtype() const { return m_qtype; }
inline bool is_qtype(q_type atype) const { return m_qtype == atype; }
inline void set_qtype(q_type atype) { m_qtype = atype; }
protected:
bjt_model_t m_model;
private:
q_type m_qtype;
};
NETLIB_OBJECT_DERIVED(QBJT, Q)
{
public:
NETLIB_CONSTRUCTOR_DERIVED(QBJT, Q)
{ }
protected:
private:
};
// -----------------------------------------------------------------------------
// nld_QBJT_switch
// -----------------------------------------------------------------------------
/*
* + - C
* B ----VVV----+ |
* | |
* Rb Rc
* Rb Rc
* Rb Rc
* | |
* +----+----+
* |
* E
*/
NETLIB_OBJECT_DERIVED(QBJT_switch, QBJT)
{
NETLIB_CONSTRUCTOR_DERIVED(QBJT_switch, QBJT)
, m_RB(*this, "m_RB", true)
, m_RC(*this, "m_RC", true)
, m_BC_dummy(*this, "m_BC", true)
, m_gB(NETLIST_GMIN_DEFAULT)
, m_gC(NETLIST_GMIN_DEFAULT)
, m_V(0.0)
, m_state_on(*this, "m_state_on", 0)
{
register_subalias("B", m_RB.m_P);
register_subalias("E", m_RB.m_N);
register_subalias("C", m_RC.m_P);
//register_term("_E1", m_RC.m_N);
//register_term("_B1", m_BC_dummy.m_P);
//register_term("_C1", m_BC_dummy.m_N);
connect(m_RB.m_N, m_RC.m_N);
connect(m_RB.m_P, m_BC_dummy.m_P);
connect(m_RC.m_P, m_BC_dummy.m_N);
}
NETLIB_RESETI();
NETLIB_UPDATEI();
NETLIB_UPDATE_PARAMI();
NETLIB_UPDATE_TERMINALSI();
nld_twoterm m_RB;
nld_twoterm m_RC;
// FIXME: this is needed so we have all terminals belong to one net list
nld_twoterm m_BC_dummy;
protected:
nl_double m_gB; // base conductance / switch on
nl_double m_gC; // collector conductance / switch on
nl_double m_V; // internal voltage source
state_var<unsigned> m_state_on;
private:
};
// -----------------------------------------------------------------------------
// nld_QBJT_EB
// -----------------------------------------------------------------------------
NETLIB_OBJECT_DERIVED(QBJT_EB, QBJT)
{
public:
NETLIB_CONSTRUCTOR_DERIVED(QBJT_EB, QBJT)
, m_gD_BC(*this, "m_D_BC")
, m_gD_BE(*this, "m_D_BE")
, m_D_CB(*this, "m_D_CB", true)
, m_D_EB(*this, "m_D_EB", true)
, m_D_EC(*this, "m_D_EC", true)
, m_alpha_f(0)
, m_alpha_r(0)
{
register_subalias("E", m_D_EB.m_P); // Cathode
register_subalias("B", m_D_EB.m_N); // Anode
register_subalias("C", m_D_CB.m_P); // Cathode
//register_term("_B1", m_D_CB.m_N); // Anode
//register_term("_E1", m_D_EC.m_P);
//register_term("_C1", m_D_EC.m_N);
connect(m_D_EB.m_P, m_D_EC.m_P);
connect(m_D_EB.m_N, m_D_CB.m_N);
connect(m_D_CB.m_P, m_D_EC.m_N);
}
protected:
NETLIB_RESETI();
NETLIB_UPDATEI();
NETLIB_UPDATE_PARAMI();
NETLIB_UPDATE_TERMINALSI();
generic_diode m_gD_BC;
generic_diode m_gD_BE;
private:
nld_twoterm m_D_CB; // gcc, gce - gcc, gec - gcc, gcc - gce | Ic
nld_twoterm m_D_EB; // gee, gec - gee, gce - gee, gee - gec | Ie
nld_twoterm m_D_EC; // 0, -gec, -gcc, 0 | 0
nl_double m_alpha_f;
nl_double m_alpha_r;
};
// ----------------------------------------------------------------------------------------
// nld_Q
// ----------------------------------------------------------------------------------------
NETLIB_UPDATE(Q)
{
// netlist().solver()->schedule1();
}
// ----------------------------------------------------------------------------------------
// nld_QBJT_switch
// ----------------------------------------------------------------------------------------
NETLIB_RESET(QBJT_switch)
{
NETLIB_NAME(Q)::reset();
m_state_on = 0;
m_RB.set(netlist().gmin(), 0.0, 0.0);
m_RC.set(netlist().gmin(), 0.0, 0.0);
m_BC_dummy.set(netlist().gmin() / 10.0, 0.0, 0.0);
}
NETLIB_UPDATE(QBJT_switch)
{
if (!m_RB.m_P.net().isRailNet())
m_RB.m_P.solve_now(); // Basis
else if (!m_RB.m_N.net().isRailNet())
m_RB.m_N.solve_now(); // Emitter
else if (!m_RC.m_P.net().isRailNet())
m_RC.m_P.solve_now(); // Collector
}
NETLIB_UPDATE_PARAM(QBJT_switch)
{
nl_double IS = m_model.m_IS;
nl_double BF = m_model.m_BF;
nl_double NF = m_model.m_NF;
//nl_double VJE = m_model.dValue("VJE", 0.75);
set_qtype((m_model.model_type() == "NPN") ? BJT_NPN : BJT_PNP);
nl_double alpha = BF / (1.0 + BF);
diode d(IS, NF);
// Assume 5mA Collector current for switch operation
m_V = d.V(0.005 / alpha);
/* Base current is 0.005 / beta
* as a rough estimate, we just scale the conductance down */
m_gB = 1.0 / (m_V/(0.005 / BF));
//m_gB = d.gI(0.005 / alpha);
if (m_gB < netlist().gmin())
m_gB = netlist().gmin();
m_gC = d.gI(0.005); // very rough estimate
}
NETLIB_UPDATE_TERMINALS(QBJT_switch)
{
const nl_double m = (is_qtype( BJT_NPN) ? 1 : -1);
const unsigned new_state = (m_RB.deltaV() * m > m_V ) ? 1 : 0;
if (m_state_on ^ new_state)
{
const nl_double gb = new_state ? m_gB : netlist().gmin();
const nl_double gc = new_state ? m_gC : netlist().gmin();
const nl_double v = new_state ? m_V * m : 0;
m_RB.set(gb, v, 0.0);
m_RC.set(gc, 0.0, 0.0);
m_state_on = new_state;
}
}
// ----------------------------------------------------------------------------------------
// nld_Q - Ebers Moll
// ----------------------------------------------------------------------------------------
NETLIB_UPDATE(QBJT_EB)
{
if (!m_D_EB.m_P.net().isRailNet())
m_D_EB.m_P.solve_now(); // Basis
else if (!m_D_EB.m_N.net().isRailNet())
m_D_EB.m_N.solve_now(); // Emitter
else
m_D_CB.m_N.solve_now(); // Collector
}
NETLIB_RESET(QBJT_EB)
{
NETLIB_NAME(Q)::reset();
}
NETLIB_UPDATE_TERMINALS(QBJT_EB)
{
const nl_double polarity = (qtype() == BJT_NPN ? 1.0 : -1.0);
m_gD_BE.update_diode(-m_D_EB.deltaV() * polarity);
m_gD_BC.update_diode(-m_D_CB.deltaV() * polarity);
const nl_double gee = m_gD_BE.G();
const nl_double gcc = m_gD_BC.G();
const nl_double gec = m_alpha_r * gcc;
const nl_double gce = m_alpha_f * gee;
const nl_double sIe = -m_gD_BE.I() + m_alpha_r * m_gD_BC.I();
const nl_double sIc = m_alpha_f * m_gD_BE.I() - m_gD_BC.I();
const nl_double Ie = (sIe + gee * m_gD_BE.Vd() - gec * m_gD_BC.Vd()) * polarity;
const nl_double Ic = (sIc - gce * m_gD_BE.Vd() + gcc * m_gD_BC.Vd()) * polarity;
m_D_EB.set_mat( gee, gec - gee, -Ie,
gce - gee, gee - gec, Ie);
m_D_CB.set_mat( gcc, gce - gcc, -Ic,
gec - gcc, gcc - gce, Ic);
m_D_EC.set_mat( 0, -gec, 0,
-gce, 0, 0);
}
NETLIB_UPDATE_PARAM(QBJT_EB)
{
nl_double IS = m_model.m_IS;
nl_double BF = m_model.m_BF;
nl_double NF = m_model.m_NF;
nl_double BR = m_model.m_BR;
nl_double NR = m_model.m_NR;
//nl_double VJE = m_model.dValue("VJE", 0.75);
set_qtype((m_model.model_type() == "NPN") ? BJT_NPN : BJT_PNP);
m_alpha_f = BF / (1.0 + BF);
m_alpha_r = BR / (1.0 + BR);
m_gD_BE.set_param(IS / m_alpha_f, NF, netlist().gmin());
m_gD_BC.set_param(IS / m_alpha_r, NR, netlist().gmin());
}
} //namespace analog
namespace devices {
NETLIB_DEVICE_IMPL_NS(analog, QBJT_EB)
NETLIB_DEVICE_IMPL_NS(analog, QBJT_switch)
}
} // namespace netlist