Listing 1--PWM constant-current-amplifier Spice circuit

*#save V(1) V(25) @R4[i] @R4[p] V(3) @R1[i] @R1[p] V(5)
*#save V(29) @R3[i] @R3[p] V(7) V(19) @R2[i] @R2[p] V(9)
*#save @Vs[i] @Vs[p] V(10) @S4[i] @S4[p] V(11) @S2[i] @S2[p]
*#save @S3[i] @S3[p] @S1[i] @S1[p] V(12) @V1[i] @V1[p] V(13)
*#save V(18) @E1[i] @E1[p] @V5[i] @V5[p] V(8) @S6[i] @S6[p]
*#save @V6[i] @V6[p] V(17) @Rload[i] @Rload[p] @Lload[i] @Rb[i] @Rb[p]
*#save @Ra[i] @Ra[p] V(16) V(14) V(20) V(21) @R8[i] @R8[p]
*#save @R9[i] @R9[p] @R10[i] @R10[p] @R11[i] @R11[p] @V3[i] @V3[p]
*#save @C1[i] @C2[i] V(24) V(18) V(26) @R12[i] @R12[p] @VEin[i]
*#save @VEin[p] @C3[i] @R14[i] @R14[p] @S5[i] @S5[p] V(15) V(30)
*#save V(2) @L1[i] @L3[i] @C4[i] @C5[i] @R13[i] @R13[p] @C6[i]
*#save @R15[i] @R15[p] @C7[i] V(23) V(29) V(6) V(4) V(21)
*#save V(22) @V2[i] @V2[p] V(27) @Vcc[i] @Vcc[p] @Rq[i] @Rq[p]
*#save V(28) @R17[i] @R17[p] @C8[i] @Rload[i]
*#VIEW TRAN Y1
*#alias Y1 @Rload[i]
.TRAN 22.2E-9 4000E-6 0 22.2E-8 UIC
.PRINT TRAN Y1
R4 1 25 0.25
R1 3 23 0.25
R3 5 29 0.25
R2 7 19 0.25
Vs 9 0 DC=80
S4 29 1 10 0 _S4_mod 
.MODEL _S4_mod SW VT=2.5 RON=1E-9 ROFF=1E9
S2 23 7 11 0 _S2_mod 
.MODEL _S2_mod SW VT=2.5 RON=1E-9 ROFF=1E9
S3 9 5 11 0 _S3_mod 
.MODEL _S3_mod SW VT=2.5 RON=1E-9 ROFF=1E9
S1 3 9 10 0 _S1_mod 
.MODEL _S1_mod SW VT=2.5 RON=1E-9 ROFF=1E9
X1 11 10 INV { }
.SUBCKT INV 1 2
* in out
B1 3 0 V= ~V(1)
RD 3 2 1
CD 2 0 .87NF
.ENDS
V1 12 0 PULSE 4 8 0 11.1E-6 11.1E-6 1E-12 22.2E-6 
E1 13 0 12 18 1E9
*#save @E1[i] @E1[p]
L1 23 4 400u
V5 15 0 DC=5
S6 11 8 0 13 _S6_mod 
.MODEL _S6_mod SW VT=2.5 RON=1E-9 ROFF=1E9
V6 0 8 DC=5
Rload 17 6 16
V2 0 22 DC=12
Lload 4 17 1m
Rb 25 0 0.1
Ra 19 0 0.1
X4 16 14 20 21 22 PA21 { }
.SUBCKT PA21 1 2 3 4 5
* PINOUT ORDER +IN -IN OUT +V -V
Q1 10 1 8 QI1
Q2 11 2 9 QI2
R3 12 8 7.39E+03
R4 12 9 7.39E+03
I2 12 5 3.61E-05
C1 12 5 2.73E-12
R5 12 5 1.11E+06
R1 4 10 8.85E+03
R2 4 11 8.85E+03
C2 10 11 9.00E-12
I1 4 5 3.70E-02
G1 6 15 11 10 1.13E-04
G2 6 15 12 15 6.36E-09
R6 6 15 1.00E+05
D1 6 15 DD
D2 15 6 DD
C3 6 7 3.00E-11
G3 15 7 15 6 8.85E+00
R7 7 15 1E3
D3 7 16 DD
V1 18 16 1.60E+00
D4 17 7 DD
V2 17 19 1.60E+00
RE1 15 0 0.001
E2 18 0 4 0 1
E3 19 0 5 0 1
R8 7 20 50
C4 20 15 3.08E-09
Q3 19 20 21 QOP
Q4 18 20 22 QON
Q5 4 23 29 QON
Q6 5 24 30 QOP
Q7 25 27 31 QLN
Q8 26 28 31 QLP
R11 21 23 1.70E-01
RCLP 29 31 1.70E-01
RCLN 30 31 1.70E-01
R13 22 24 1.70E-01
D5 23 25 DL
D6 26 24 DL
R9 27 29 1E3
R10 28 30 1E3
I3 18 23 7.92E-03
I4 24 19 7.92E-03
R15 31 3 5.42E-01
RSN 3 34 1
CSN 34 5 0.1E-6
.MODEL DD D(CJO=0.1PF IS=1E-17)
.MODEL DL D(CJO=3PF IS=1E-13)
.MODEL QI1 NPN (BF=6.55E+02 IS=8E-16)
.MODEL QI2 NPN (BF=4.24E+02 IS=8.46E-16)
.MODEL QOP PNP (BF=4.64E+02 IS=1E-14)
.MODEL QON NPN (BF=4.64E+02 IS=1E-14)
.MODEL QLN NPN (BF=100 IS=1E-14)
.MODEL QLP PNP (BF=100 IS=1E-14)
.ENDS
R8 16 30 10K
R9 14 2 10K
R10 14 20 200K
R11 16 0 200K
Vcc 27 0 DC=12
V3 21 0 DC=12
C1 16 0 180p
C2 14 20 180p
Rq 27 0 600
X3 0 24 18 21 22 PA21 { }
R12 24 26 10K
VEin 26 0 DC=10
C3 18 24 71n
S5 15 11 13 0 _S5_mod 
.MODEL _S5_mod SW VT=2.5 RON=1E-9 ROFF=1E9
L3 29 6 400u
R14 24 20 10K
C4 4 0 3.1u
C5 0 6 3.1u
R17 28 6 16
R13 30 25 100
C6 30 0 0.35u
C8 4 28 3.9u
R15 2 19 100
C7 2 0 0.35u
.END