188 lines
3.6 KiB
C
188 lines
3.6 KiB
C
// license:GPL-2.0+
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// copyright-holders:Couriersud
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/*
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* opamp.c
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*
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*/
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#include "netlist/devices/net_lib.h"
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NETLIST_START(main)
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/* Standard stuff */
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CLOCK(clk, 1000) // 1000 Hz
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SOLVER(Solver, 480000)
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PARAM(Solver.ACCURACY, 1e-10)
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PARAM(Solver.NR_LOOPS, 30000 )
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//PARAM(Solver.CONVERG, 1.0)
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PARAM(Solver.GS_LOOPS, 30)
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// Tie up +5 to opamps thought it's not currently needed
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// Stay compatible
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ANALOG_INPUT(V5, 5)
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NET_C(op.VCC, V5)
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NET_C(op1.VCC, V5)
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/* Opamp wired as impedance changer */
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SUBMODEL(opamp, op)
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NET_C(op.GND, GND)
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NET_C(op.PLUS, clk)
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NET_C(op.MINUS, op.OUT)
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SUBMODEL(opamp, op1)
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/* Wired as inverting amplifier connected to output of first opamp */
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RES(R1, 100000)
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RES(R2, 200000)
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NET_C(op1.GND, GND)
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NET_C(op1.PLUS, GND)
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NET_C(op1.MINUS, R2.2)
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NET_C(op1.MINUS, R1.2)
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NET_C(op.OUT, R1.1)
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NET_C(op1.OUT, R2.1)
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RES(RL, 1000)
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NET_C(RL.2, GND)
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NET_C(RL.1, op1.OUT)
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LOG(logX, op1.OUT)
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LOG(logY, clk)
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NETLIST_END()
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NETLIST_START(opamp)
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/* Opamp model from
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*
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* http://www.ecircuitcenter.com/Circuits/opmodel1/opmodel1.htm
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*
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* Bandwidth 10Mhz
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*
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*/
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/* Terminal definitions for calling netlists */
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ALIAS(PLUS, G1.IP) // Positive input
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ALIAS(MINUS, G1.IN) // Negative input
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ALIAS(OUT, EBUF.OP) // Opamp output ...
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ALIAS(GND, EBUF.ON) // GND terminal
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ALIAS(VCC, DUMMY.I) // VCC terminal
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DUMMY_INPUT(DUMMY)
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/* The opamp model */
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LVCCS(G1)
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PARAM(G1.G, 0.0021)
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PARAM(G1.CURLIM, 0.002)
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RES(RP1, 1e7)
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CAP(CP1, 0.00333e-6)
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VCVS(EBUF)
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PARAM(EBUF.RO, 50)
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PARAM(EBUF.G, 1)
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// NET_C(EBUF.ON, GND)
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NET_C(G1.ON, GND)
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NET_C(RP1.2, GND)
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NET_C(CP1.2, GND)
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NET_C(EBUF.IN, GND)
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NET_C(RP1.1, G1.OP)
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NET_C(CP1.1, RP1.1)
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NET_C(EBUF.IP, RP1.1)
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NETLIST_END()
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NETLIST_START(opamp_mod)
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/* Opamp model from
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*
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* http://www.ecircuitcenter.com/Circuits/opmodel1/opmodel1.htm
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*
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* MB3614 Unit Gain frequency is about 500 kHz and the first pole frequency
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* about 5 Hz. We have to keep the Unity Gain Frequency below our sampling
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* frequency of 24 Khz.
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*
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* Simple Opamp Model Calculation
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*
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* First Pole Frequency 5 Hz
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* Unity Gain Frequency 11,000 Hz
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* RP 100,000 Ohm
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* DC Gain / Aol 2200
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* CP 0.318 uF
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* KG 0.022
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*
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*/
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/* Terminal definitions for calling netlists */
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ALIAS(PLUS, G1.IP) // Positive input
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ALIAS(MINUS, G1.IN) // Negative input
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ALIAS(OUT, EBUF.OP) // Opamp output ...
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AFUNC(fUH, 1, "A0 1.2 -")
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AFUNC(fUL, 1, "A0 1.2 +")
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ALIAS(VCC, fUH.A0) // VCC terminal
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ALIAS(GND, fUL.A0) // VGND terminal
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AFUNC(fVREF, 2, "A0 A1 + 0.5 *")
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NET_C(fUH.A0, fVREF.A0)
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NET_C(fUL.A0, fVREF.A1)
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NET_C(EBUF.ON, fVREF)
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/* The opamp model */
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LVCCS(G1)
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PARAM(G1.RI, RES_K(1000))
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#if 0
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PARAM(G1.G, 0.0022)
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RES(RP1, 1e6)
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CAP(CP1, 0.0318e-6)
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#else
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PARAM(G1.G, 0.002)
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PARAM(G1.CURLIM, 0.002)
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RES(RP1, 9.5e6)
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CAP(CP1, 0.0033e-6)
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#endif
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VCVS(EBUF)
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PARAM(EBUF.RO, 50)
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PARAM(EBUF.G, 1)
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NET_C(G1.ON, fVREF)
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NET_C(RP1.2, fVREF)
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NET_C(CP1.2, fVREF)
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NET_C(EBUF.IN, fVREF)
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NET_C(RP1.1, G1.OP)
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NET_C(CP1.1, RP1.1)
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DIODE(DP,"D(IS=1e-15 N=1)")
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DIODE(DN,"D(IS=1e-15 N=1)")
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#if 1
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NET_C(DP.K, fUH.Q)
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NET_C(fUL.Q, DN.A)
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NET_C(DP.A, DN.K, RP1.1)
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#else
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/*
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* This doesn't add any performance by decreasing iteration loops.
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* To the contrary, it significantly decreases iterations
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*/
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RES(RH1, 0.1)
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RES(RL1, 0.1)
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NET_C(DP.K, RH1.1)
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NET_C(RH1.2, fUH.Q)
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NET_C(fUL.Q, RL1.1)
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NET_C(RL1.2, DN.A)
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NET_C(DP.A, DN.K, RP1.1)
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#endif
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NET_C(EBUF.IP, RP1.1)
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NETLIST_END()
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