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/*
 * opamp.c
 *
 */


#include "netlist/devices/net_lib.h"

NETLIST_START(main)

    /* Standard stuff */

    CLOCK(clk, 10000) // 1000 Hz
    SOLVER(Solver, 48000)
    ANALOG_INPUT(V5, 5)
    PARAM(Solver.ACCURACY, 1e-6)
    PARAM(Solver.DYNAMIC_TS, 0)
    PARAM(Solver.SOR_FACTOR, 1.0)
    //PARAM(Solver.CONVERG, 1.0)
    PARAM(Solver.GS_LOOPS, 5)

    SUBMODEL(op1, opamp_fast)
    /* Wired as non - inverting amplifier like in LM3900 datasheet */

    RES(R1, 25000)
    RES(R2, 100000)
    RES(R3, 200000)
    CAP(C1, CAP_U(0.05))

    NET_C(clk, C1.1)
    NET_C(C1.2, R1.1)

    NET_C(op1.VM, GND)
    NET_C(op1.VP, V5    )
    NET_C(op1.PLUS, R1.2, R3.1)
    NET_C(R3.2, V5)
    //NET_C(R3.2, GND)
    NET_C(op1.MINUS, R2.2)
    NET_C(op1.OUT, R2.1)

    RES(RL, 10000)
    NET_C(RL.2, GND)
    NET_C(RL.1, op1.OUT)

    LOG(logX, op1.OUT)
    LOG(logY, clk)
NETLIST_END()

NETLIST_START(opamp)

    /* Opamp model from
     *
     * http://www.ecircuitcenter.com/Circuits/opmodel1/opmodel1.htm
     *
     * Bandwidth 10Mhz
     *
     */

    /* Terminal definitions for calling netlists */

    ALIAS(PLUS, G1.IP) // Positive input
    ALIAS(MINUS, G2.IN) // Negative input
    ALIAS(OUT, EBUF.OP) // Opamp output ...
    ALIAS(VM, EBUF.ON)  // V- terminal
    ALIAS(VP, DUMMY.I)  // V+ terminal

    DUMMY_INPUT(DUMMY)

    /* The opamp model */

    CCCS(G1)
    CCCS(G2)
    //PARAM(G1.G, 100)  // typical OP-AMP amplification 100 * 1000 = 100000
    PARAM(G1.G, 1000000)  // typical OP-AMP amplification 100 * 1000 = 100000
    PARAM(G2.G, 1000000)  // typical OP-AMP amplification 100 * 1000 = 100000
    RES(RP1, 1000)
    CAP(CP1, 1.59e-6)   // <== change to 1.59e-3 for 10Khz bandwidth
    VCVS(EBUF)
    PARAM(EBUF.RO, 50)
    PARAM(EBUF.G, 1)

//    NET_C(EBUF.ON, GND)

    NET_C(G1.ON, GND)
    NET_C(G2.ON, GND)
    NET_C(RP1.2, GND)
    NET_C(CP1.2, GND)
    NET_C(EBUF.IN, GND)

    NET_C(G1.IN, G2.IP, GND)

    NET_C(RP1.1, G1.OP)
    NET_C(RP1.1, G2.OP)
    NET_C(CP1.1, RP1.1)
    NET_C(EBUF.IP, RP1.1)

NETLIST_END()

NETLIST_START(opamp_fast)

    /*
     *  Fast norton opamp model without bandwidth
     */

    /* Terminal definitions for calling netlists */

    ALIAS(PLUS, R1.1) // Positive input
    ALIAS(MINUS, R2.1) // Negative input
    ALIAS(OUT, G1.OP) // Opamp output ...
    ALIAS(VM, G1.ON)  // V- terminal
    ALIAS(VP, DUMMY.I)  // V+ terminal

    DUMMY_INPUT(DUMMY)

    /* The opamp model */

    RES(R1, 1)
    RES(R2, 1)
    NET_C(R1.1, G1.IP)
    NET_C(R2.1, G1.IN)
    NET_C(R1.2, R2.2, G1.ON)
    VCVS(G1)
    PARAM(G1.G, 1000000)
    PARAM(G1.RO, RES_K(8))

NETLIST_END()