* SPICE netlist
R1 N002 N013 50
R2 N002 N012 50
R3 N013 N012 50
V1 N012 0 SINE(0 0.316 2072000000)
V2 N011 N014 PULSE(0 4 0 5n 5n 99.68n 199.36n)
Q1 N008 N011 N014 0 NPN
R4 N014 N019 850
R5 N004 N008 850
R6 N004 N009 650
R7 N015 N019 650
C1 N009 N008 150p
C2 N015 N014 150p
R8 N009 0 50
R9 0 N015 50
D2 N009 N015 D
C3 N002 N009 5p
C4 N015 N013 5p
V3 N004 0 15
V4 N019 0 -15
R10 N002 0 50
R11 0 N013 50
D3 N005 N002 D
D4 N013 N017 D
C5 N005 0 5p
C6 0 N017 5p
R12 N006 N005 300
R13 N018 N017 300
R14 N006 N007 50k
R15 N007 N018 50k
C7 N007 N006 10n
C8 N007 N018 10n
V5 N003 0 15
V6 N016 0 -15
C9 0 N003 10n
C10 N016 0 10n
R16 N001 N010 680k
R17 N001 0 25k
XU1 N007 N001 N003 N016 N010 AD746 ;pnba In+)In-)V+)V-)OUT
D1 N014 N011 D
.tran 10u uic

* LTspice schematic (.asc)
Version 4
SHEET 1 3072 848
WIRE 1520 -312 1520 -344
WIRE 1520 -312 1104 -312
WIRE 256 -280 -1088 -280
WIRE 1328 -216 1200 -216
WIRE 1520 -216 1520 -312
WIRE -160 -184 -272 -184
WIRE -32 -184 -160 -184
WIRE 256 -184 256 -280
WIRE 464 -184 256 -184
WIRE 560 -184 464 -184
WIRE 688 -184 624 -184
WIRE 784 -184 768 -184
WIRE 928 -184 848 -184
WIRE 784 -104 784 -184
WIRE -160 -56 -160 -104
WIRE -128 -56 -160 -56
WIRE -32 -56 -32 -104
WIRE -32 -56 -64 -56
WIRE 64 -56 -32 -56
WIRE 256 -56 256 -120
WIRE 256 -56 64 -56
WIRE 304 -56 256 -56
WIRE -160 8 -160 -56
WIRE 304 8 304 -56
WIRE 1328 8 1328 -216
WIRE 784 24 784 -24
WIRE 928 24 928 -184
WIRE 928 24 784 24
WIRE 1104 24 1104 -312
WIRE 1296 24 1104 24
WIRE -1088 40 -1088 -280
WIRE -1088 40 -1152 40
WIRE 64 40 64 24
WIRE 64 40 16 40
WIRE 1520 40 1520 -136
WIRE 1520 40 1360 40
WIRE -304 56 -464 56
WIRE -224 56 -304 56
WIRE 64 56 64 40
WIRE 928 56 928 24
WIRE 1296 56 928 56
WIRE 784 72 784 24
WIRE -1232 88 -1232 40
WIRE -1232 88 -1536 88
WIRE -1232 120 -1232 88
WIRE -1088 120 -1152 120
WIRE -304 136 -304 120
WIRE -304 136 -464 136
WIRE -160 136 -160 104
WIRE -160 136 -304 136
WIRE -128 136 -160 136
WIRE -32 136 -64 136
WIRE 64 136 -32 136
WIRE 256 136 64 136
WIRE 304 136 304 72
WIRE 304 136 256 136
WIRE -160 200 -160 136
WIRE -32 200 -32 136
WIRE 256 200 256 136
WIRE 1328 200 1328 72
WIRE 1328 248 1328 200
WIRE 400 264 256 264
WIRE 560 264 400 264
WIRE 688 264 624 264
WIRE 784 264 784 152
WIRE 784 264 768 264
WIRE 928 264 928 56
WIRE 928 264 848 264
WIRE -96 280 -160 280
WIRE -32 280 -96 280
WIRE -1088 424 -1088 120
WIRE 256 424 256 264
WIRE 256 424 -1088 424
FLAG -1536 168 0
FLAG 16 40 0
FLAG -96 360 0
FLAG -272 -104 0
FLAG 400 184 0
FLAG 464 -104 0
FLAG 624 200 0
FLAG 624 -120 0
FLAG 1200 -136 0
FLAG 1328 328 0
FLAG 1392 -216 0
FLAG 1264 200 0
FLAG 1520 -424 0
SYMBOL res -1104 24 R0
SYMATTR InstName R1
SYMATTR Value 50
SYMBOL res -1136 24 R90
SYMATTR InstName R2
SYMATTR Value 50
SYMBOL res -1136 104 R90
SYMATTR InstName R3
SYMATTR Value 50
SYMBOL voltage -1536 72 R0
SYMATTR InstName V1
SYMATTR Value SINE(0 0.316 2072000000)
SYMBOL voltage -464 40 R0
SYMATTR InstName V2
SYMATTR Value PULSE(0 4 0 5n 5n 99.68n 199.36n)
SYMBOL npn -224 8 R0
SYMATTR InstName Q1
SYMBOL res -176 184 R0
SYMATTR InstName R4
SYMATTR Value 850
SYMBOL res -176 -200 R0
SYMATTR InstName R5
SYMATTR Value 850
SYMBOL res -48 -200 R0
SYMATTR InstName R6
SYMATTR Value 650
SYMBOL res -48 184 R0
SYMATTR InstName R7
SYMATTR Value 650
SYMBOL cap -64 -72 R90
SYMATTR InstName C1
SYMATTR Value 150p
SYMBOL cap -64 120 R90
SYMATTR InstName C2
SYMATTR Value 150p
SYMBOL res 48 -72 R0
SYMATTR InstName R8
SYMATTR Value 50
SYMBOL res 48 40 R0
SYMATTR InstName R9
SYMATTR Value 50
SYMBOL diode 288 8 R0
SYMATTR InstName D2
SYMBOL cap 240 -184 R0
SYMATTR InstName C3
SYMATTR Value 5p
SYMBOL cap 240 200 R0
SYMATTR InstName C4
SYMATTR Value 5p
SYMBOL voltage -272 -200 R0
SYMATTR InstName V3
SYMATTR Value 15
SYMBOL voltage -96 264 R0
SYMATTR InstName V4
SYMATTR Value -15
SYMBOL res 448 -200 R0
SYMATTR InstName R10
SYMATTR Value 50
SYMBOL res 384 168 R0
SYMATTR InstName R11
SYMATTR Value 50
SYMBOL diode 624 -200 R90
SYMATTR InstName D3
SYMBOL diode 560 280 R270
SYMATTR InstName D4
SYMBOL cap 608 -184 R0
SYMATTR InstName C5
SYMATTR Value 5p
SYMBOL cap 608 200 R0
SYMATTR InstName C6
SYMATTR Value 5p
SYMBOL res 784 -200 R90
SYMATTR InstName R12
SYMATTR Value 300
SYMBOL res 784 248 R90
SYMATTR InstName R13
SYMATTR Value 300
SYMBOL res 768 -120 R0
SYMATTR InstName R14
SYMATTR Value 50k
SYMBOL res 768 56 R0
SYMATTR InstName R15
SYMATTR Value 50k
SYMBOL cap 848 -200 R90
SYMATTR InstName C7
SYMATTR Value 10n
SYMBOL cap 848 248 R90
SYMATTR InstName C8
SYMATTR Value 10n
SYMBOL voltage 1200 -232 R0
SYMATTR InstName V5
SYMATTR Value 15
SYMBOL voltage 1328 232 R0
SYMATTR InstName V6
SYMATTR Value -15
SYMBOL cap 1392 -232 R90
SYMATTR InstName C9
SYMATTR Value 10n
SYMBOL cap 1328 184 R90
SYMATTR InstName C10
SYMATTR Value 10n
SYMBOL res 1504 -232 R0
SYMATTR InstName R16
SYMATTR Value 680k
SYMBOL res 1536 -328 R180
SYMATTR InstName R17
SYMATTR Value 25k
SYMBOL OpAmps\\AD744 1328 -24 R0
SYMATTR InstName U1
SYMBOL diode -288 120 R180
SYMATTR InstName D1