* SPICE netlist
Q1 N006 INA N020 0 2N3904
R1 N020 N022 56
R2 N021 N022 56
Q2 N018 INB N021 0 2N3904
Q3 N022 N023 N025 0 2N3904
Q4 N001 N006 N011 0 2N3904
Q5 N001 N018 N012 0 2N3904
Q6 N003 N011 N015 0 2N3904
Q7 N004 N012 N014 0 2N3904
Q8 N001 N003 SENSE_OUT 0 2N3904
Q9 N001 N004 SENSE_OUT 0 2N3904
R3 N025 N027 600
R4 N011 N027 6.8k
R5 N012 N027 6.8k
R6 N026 N027 300
R7 N015 N019 70
R8 N014 N019 70
R9 N019 N024 1k
R10 SENSE_OUT 0 5k
R11 N001 N003 1.2k
R12 N001 N004 1.2k
R13 N005 N018 1k
R14 N005 N006 1k
R15 N001 N005 1.7k
VP V+ 0 12
VN 0 V- 12
VINA INA 0 PWL file=ampl_train.pwl
VINB INB 0 0
Q14 N023 N023 N026 0 2N3904
R17 V_REF 0 3k
R19 N001 V_REF 1.3k
VP1 VCC 0 3.3
R20 N013 0 2k
Q18 N013 N009 N002 0 2N3906
D1 N013 N009 BAT54
R25 N016 0 200
Q11 OUT1 N017 N010 0 2N3906
D4 OUT1 N017 BAT54
R26 OUT1 0 100
Q10 VCC N007 N016 0 2N3904
D2 N007 VCC BAT54
Q13 0 V_REF N002 0 2N3906
R18 N001 N002 1k
R23 N007 N013 1k
R24 V+ N001 1m
R28 N027 V- 1m
D3 VCC N010 1N914
R22 N017 N016 1k
R27 N010 0 100
R30 N009 N008 100
Q15 N001 SENSE_OUT N008 0 2N3904
R29 N008 0 1k
R16 N001 N023 2k
I1 N024 N027 9m
.dc VINA -100m 100m 0.1m
.step temp -25 125 25

* LTspice schematic (.asc)
Version 4.1
SHEET 1 3840 2256
WIRE -1872 -1128 -1920 -1128
WIRE -1824 -1128 -1872 -1128
WIRE -1712 -1128 -1760 -1128
WIRE -1680 -1128 -1712 -1128
WIRE -1504 -1128 -1584 -1128
WIRE -1280 -1128 -1504 -1128
WIRE -1040 -1128 -1088 -1128
WIRE -992 -1128 -1040 -1128
WIRE -1344 -1064 -1408 -1064
WIRE -1280 -1064 -1344 -1064
WIRE -1920 -1000 -1920 -1128
WIRE -1760 -1000 -1760 -1128
WIRE -1584 -1000 -1584 -1128
WIRE -1408 -1000 -1408 -1064
WIRE -1088 -1000 -1088 -1128
WIRE -1520 -488 -1568 -488
WIRE -1472 -488 -1520 -488
WIRE -1296 -488 -1392 -488
WIRE -960 -488 -1296 -488
WIRE -880 -488 -960 -488
WIRE -816 -488 -880 -488
WIRE -704 -488 -816 -488
WIRE -608 -488 -704 -488
WIRE -448 -488 -608 -488
WIRE -304 -488 -448 -488
WIRE 32 -488 -304 -488
WIRE 208 -488 32 -488
WIRE 448 -488 208 -488
WIRE 448 -472 448 -488
WIRE 208 -440 208 -488
WIRE -1296 -392 -1296 -488
WIRE -704 -392 -704 -488
WIRE -304 -392 -304 -488
WIRE 448 -376 448 -392
WIRE 816 -376 448 -376
WIRE 1632 -376 1360 -376
WIRE 1760 -376 1632 -376
WIRE 448 -312 448 -376
WIRE -816 -264 -816 -488
WIRE 208 -264 208 -360
WIRE 384 -264 208 -264
WIRE -608 -248 -608 -488
WIRE -448 -248 -448 -488
WIRE -704 -200 -704 -312
WIRE -672 -200 -704 -200
WIRE -304 -200 -304 -312
WIRE -304 -200 -384 -200
WIRE -1296 -184 -1296 -312
WIRE -1296 -184 -1408 -184
WIRE -1216 -184 -1296 -184
WIRE -1408 -136 -1408 -184
WIRE -1216 -136 -1216 -184
WIRE 32 -136 32 -488
WIRE -608 -120 -608 -152
WIRE -528 -120 -608 -120
WIRE -448 -120 -448 -152
WIRE -448 -120 -528 -120
WIRE 1760 -104 1760 -376
WIRE -528 -88 -528 -120
WIRE -192 -88 -528 -88
WIRE -32 -88 -192 -88
WIRE -960 -56 -960 -488
WIRE -528 -40 -528 -88
WIRE -1408 -8 -1408 -56
WIRE -1024 -8 -1408 -8
WIRE 816 8 816 -376
WIRE -704 24 -704 -200
WIRE -304 24 -304 -200
WIRE 1248 40 1216 40
WIRE 1360 40 1360 -376
WIRE 1360 40 1312 40
WIRE 32 56 32 -40
WIRE 608 56 32 56
WIRE 720 56 688 56
WIRE 752 56 720 56
WIRE 1760 56 1760 -40
WIRE 1760 56 1568 56
WIRE -960 72 -960 40
WIRE -768 72 -960 72
WIRE -144 72 -240 72
WIRE 1360 88 1360 40
WIRE 720 136 720 56
WIRE 736 136 720 136
WIRE 816 136 816 104
WIRE 816 136 800 136
WIRE 944 136 816 136
WIRE 1216 136 1216 40
WIRE 1216 136 1024 136
WIRE 1296 136 1216 136
WIRE -528 152 -528 40
WIRE 1760 152 1760 56
WIRE -880 168 -880 -488
WIRE -304 184 -304 120
WIRE -704 200 -704 120
WIRE 1360 200 1360 184
WIRE 1456 200 1360 200
WIRE 1632 200 1536 200
WIRE 1696 200 1632 200
WIRE -1216 216 -1216 -56
WIRE -944 216 -1216 216
WIRE 208 296 208 -264
WIRE 1632 296 1632 200
WIRE 1648 296 1632 296
WIRE 1760 296 1760 248
WIRE 1760 296 1712 296
WIRE -1408 312 -1408 -8
WIRE -1216 312 -1216 216
WIRE 32 312 32 56
WIRE -704 344 -704 280
WIRE -512 344 -704 344
WIRE -304 344 -304 264
WIRE -304 344 -512 344
WIRE -1792 360 -1840 360
WIRE -1472 360 -1792 360
WIRE -1056 360 -1152 360
WIRE -880 392 -880 264
WIRE -144 392 -144 72
WIRE -144 392 -880 392
WIRE 1760 392 1760 296
WIRE 1840 392 1760 392
WIRE 1920 392 1840 392
WIRE 208 408 208 296
WIRE 1568 440 1568 56
WIRE -1408 456 -1408 408
WIRE -1216 456 -1216 408
WIRE -512 456 -512 344
WIRE 816 456 816 136
WIRE 1760 456 1760 392
WIRE 1360 504 1360 200
WIRE -1408 600 -1408 536
WIRE -1296 600 -1408 600
WIRE -1216 600 -1216 536
WIRE -1216 600 -1296 600
WIRE 32 600 32 392
WIRE 208 600 208 488
WIRE 448 600 448 -216
WIRE 816 600 816 536
WIRE 1360 616 1360 584
WIRE 1568 616 1568 520
WIRE 1760 616 1760 536
WIRE -1792 632 -1840 632
WIRE -1056 632 -1056 360
WIRE -1056 632 -1792 632
WIRE -1296 696 -1296 600
WIRE -1152 744 -1232 744
WIRE -1040 744 -1152 744
WIRE -816 744 -816 -184
WIRE -816 744 -1040 744
WIRE -512 744 -512 536
WIRE -1152 824 -1152 744
WIRE -1040 872 -1040 744
WIRE -1040 872 -1088 872
WIRE -960 904 -960 72
WIRE -880 904 -880 392
WIRE -1296 936 -1296 792
WIRE -1152 1000 -1152 920
WIRE -1536 1128 -1568 1128
WIRE -1488 1128 -1536 1128
WIRE -1296 1128 -1296 1016
WIRE -1296 1128 -1408 1128
WIRE -1152 1128 -1152 1080
WIRE -1152 1128 -1296 1128
WIRE -960 1128 -960 984
WIRE -960 1128 -1152 1128
WIRE -880 1128 -880 984
WIRE -880 1128 -960 1128
WIRE -512 1128 -512 824
WIRE -512 1128 -880 1128
WIRE 32 1128 -512 1128
FLAG -192 -88 SENSE_OUT
FLAG -1792 360 INA
FLAG -1792 632 INB
FLAG -1520 -488 V+
FLAG -1536 1128 V-
FLAG -1920 -920 0
FLAG -1584 -920 0
FLAG -1760 -920 0
FLAG -1408 -920 0
FLAG -1872 -1128 V+
FLAG -1712 -1128 V-
FLAG -1504 -1128 INA
FLAG -1344 -1064 INB
FLAG -528 152 0
FLAG 208 296 V_REF
FLAG 1840 392 OUT1
FLAG -1088 -920 0
FLAG -1040 -1128 VCC
FLAG 816 600 0
FLAG 1360 616 0
FLAG 1632 -376 VCC
FLAG 1760 616 0
FLAG 208 600 0
FLAG 448 600 0
FLAG 1568 616 0
FLAG 32 600 0
SYMBOL npn -1472 312 R0
SYMATTR InstName Q1
SYMATTR Value 2N3904
SYMBOL res -1424 440 R0
SYMATTR InstName R1
SYMATTR Value 56
SYMBOL res -1232 440 R0
SYMATTR InstName R2
SYMATTR Value 56
SYMBOL npn -1152 312 M0
SYMATTR InstName Q2
SYMATTR Value 2N3904
SYMBOL npn -1232 696 M0
SYMATTR InstName Q3
SYMATTR Value 2N3904
SYMBOL npn -1024 -56 R0
SYMATTR InstName Q4
SYMATTR Value 2N3904
SYMBOL npn -944 168 R0
SYMATTR InstName Q5
SYMATTR Value 2N3904
SYMBOL npn -768 24 R0
SYMATTR InstName Q6
SYMATTR Value 2N3904
SYMBOL npn -240 24 M0
SYMATTR InstName Q7
SYMATTR Value 2N3904
SYMBOL npn -672 -248 R0
SYMATTR InstName Q8
SYMATTR Value 2N3904
SYMBOL npn -384 -248 M0
SYMATTR InstName Q9
SYMATTR Value 2N3904
SYMBOL res -1312 920 R0
SYMATTR InstName R3
SYMATTR Value 600
SYMBOL res -976 888 R0
SYMATTR InstName R4
SYMATTR Value 6.8k
SYMBOL res -896 888 R0
SYMATTR InstName R5
SYMATTR Value 6.8k
SYMBOL res -1168 984 R0
SYMATTR InstName R6
SYMATTR Value 300
SYMBOL res -720 184 R0
SYMATTR InstName R7
SYMATTR Value 70
SYMBOL res -320 168 R0
SYMATTR InstName R8
SYMATTR Value 70
SYMBOL res -528 440 R0
SYMATTR InstName R9
SYMATTR Value 1k
SYMBOL res -544 -56 R0
SYMATTR InstName R10
SYMATTR Value 5k
SYMBOL res -720 -408 R0
SYMATTR InstName R11
SYMATTR Value 1.2k
SYMBOL res -320 -408 R0
SYMATTR InstName R12
SYMATTR Value 1.2k
SYMBOL res -1232 -152 R0
SYMATTR InstName R13
SYMATTR Value 1k
SYMBOL res -1424 -152 R0
SYMATTR InstName R14
SYMATTR Value 1k
SYMBOL res -1312 -408 R0
SYMATTR InstName R15
SYMATTR Value 1.7k
SYMBOL voltage -1920 -1016 R0
SYMATTR InstName VP
SYMATTR Value 12
SYMBOL voltage -1760 -904 R180
SYMATTR InstName VN
SYMATTR Value 12
SYMBOL voltage -1584 -1016 R0
SYMATTR InstName VINA
SYMATTR Value PWL file=ampl_train.pwl
SYMBOL voltage -1408 -1016 R0
SYMATTR InstName VINB
SYMATTR Value 0
SYMBOL npn -1088 824 M0
SYMATTR InstName Q14
SYMATTR Value 2N3904
SYMBOL res 192 392 R0
SYMATTR InstName R17
SYMATTR Value 3k
SYMBOL res 192 -456 R0
SYMATTR InstName R19
SYMATTR Value 1.3k
SYMBOL voltage -1088 -1016 R0
SYMATTR InstName VP1
SYMATTR Value 3.3
SYMBOL res 800 440 R0
SYMATTR InstName R20
SYMATTR Value 2k
SYMBOL pnp 752 104 M180
SYMATTR InstName Q18
SYMATTR Value 2N3906
SYMBOL schottky 800 120 R90
SYMATTR InstName D1
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 1344 488 R0
SYMATTR InstName R25
SYMATTR Value 200
SYMBOL pnp 1696 248 M180
SYMATTR InstName Q11
SYMATTR Value 2N3906
SYMBOL schottky 1712 312 M270
SYMATTR InstName D4
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 1744 440 R0
SYMATTR InstName R26
SYMATTR Value 100
SYMBOL npn 1296 88 R0
SYMATTR InstName Q10
SYMATTR Value 2N3904
SYMBOL diode 1248 56 R270
SYMATTR InstName D2
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL pnp 384 -216 M180
SYMATTR InstName Q13
SYMATTR Value 2N3906
SYMBOL res 432 -488 R0
SYMATTR InstName R18
SYMATTR Value 1k
SYMBOL res 1040 120 R90
SYMATTR InstName R23
SYMATTR Value 1k
SYMBOL res -1488 -472 R270
SYMATTR InstName R24
SYMATTR Value 1m
SYMBOL res -1392 1112 R90
SYMATTR InstName R28
SYMATTR Value 1m
SYMBOL diode 1744 -104 R0
SYMATTR InstName D3
SYMATTR Value 1N914
SYMBOL res 1552 184 R90
SYMATTR InstName R22
SYMATTR Value 1k
SYMBOL res 1552 424 R0
SYMATTR InstName R27
SYMATTR Value 100
SYMBOL res 704 40 R90
SYMATTR InstName R30
SYMATTR Value 100
SYMBOL npn -32 -136 R0
SYMATTR InstName Q15
SYMATTR Value 2N3904
SYMBOL res 16 296 R0
SYMATTR InstName R29
SYMATTR Value 1k
SYMBOL res -832 -280 R0
SYMATTR InstName R16
SYMATTR Value 2k
SYMBOL current -512 744 R0
SYMATTR InstName I1
SYMATTR Value 9m