* SPICE netlist
V1 N002 0 9
XU1 N005 N003 N002 0 OUT LT1018 ;pnba In+)In-)V+)V-)OUT
R1 N005 N009 1Meg
R2 N009 0 10K
D1 N008 N009 1N4148
D2 N003 N001 1N4148
R3 N001 N002 47K
D3 N001 0 1N4148
C1 OUT N001 .001
R4 OUT N001 3Meg
D4 OUT N004 1N4148
R5 N002 N004 220K
D5 N004 N007 1N4148
D6 0 N007 LT1034
XU2 N007 N010 N002 0 N008 LT1018 ;pnba In+)In-)V+)V-)OUT
R6 OUT N010 330K
C2 0 N010 .1
C3 0 N003 .1
Q1 N003 N006 0 0 2N3904
R7 N008 N006 100K
R8 N003 IN 1.2Meg
V2 IN 0 PWL(0 0 .5 1)
C4 OUT N009 220p
C5 0 N004 2.2
C6 N010 N008 100p
.tran .5 startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1152 720
WIRE 96 -344 64 -344
WIRE 224 -344 176 -344
WIRE -144 -248 -176 -248
WIRE -48 -248 -80 -248
WIRE 64 -248 64 -344
WIRE 64 -248 -48 -248
WIRE 128 -248 64 -248
WIRE 224 -248 224 -344
WIRE 224 -248 192 -248
WIRE 288 -248 224 -248
WIRE 64 -232 64 -248
WIRE -48 -168 -48 -248
WIRE 64 -136 64 -152
WIRE 176 -136 64 -136
WIRE 336 -136 176 -136
WIRE 576 -136 336 -136
WIRE 336 -120 336 -136
WIRE 576 -120 576 -136
WIRE 64 -56 64 -136
WIRE -448 -40 -576 -40
WIRE -272 -40 -368 -40
WIRE -176 -40 -272 -40
WIRE -48 -40 -48 -104
WIRE -48 -40 -176 -40
WIRE 32 -40 -48 -40
WIRE -576 -24 -576 -40
WIRE -272 -24 -272 -40
WIRE -176 -24 -176 -40
WIRE 224 -24 224 -248
WIRE 224 -24 96 -24
WIRE 240 -24 224 -24
WIRE 336 -24 336 -40
WIRE 336 -24 304 -24
WIRE 400 -24 336 -24
WIRE 496 -24 464 -24
WIRE 576 -24 576 -40
WIRE 32 -8 -48 -8
WIRE -48 8 -48 -8
WIRE 336 8 336 -24
WIRE -336 24 -352 24
WIRE 64 24 64 8
WIRE -576 72 -576 56
WIRE -176 72 -176 40
WIRE -272 88 -272 72
WIRE 336 88 336 72
WIRE 464 88 336 88
WIRE -144 104 -176 104
WIRE -48 104 -48 88
WIRE -48 104 -80 104
WIRE 32 104 -48 104
WIRE 224 104 224 -24
WIRE 224 104 96 104
WIRE -48 120 -48 104
WIRE 224 120 224 104
WIRE 336 120 336 88
WIRE 336 200 336 184
WIRE -48 216 -48 200
WIRE 32 216 16 216
WIRE 224 216 224 200
WIRE 224 216 96 216
WIRE 224 264 224 216
WIRE 256 264 224 264
WIRE 336 264 320 264
WIRE 176 280 176 -136
WIRE 224 296 224 264
WIRE 224 296 208 296
WIRE -352 312 -352 24
WIRE -320 312 -352 312
WIRE -176 312 -176 104
WIRE -176 312 -240 312
WIRE 16 312 16 216
WIRE 16 312 -176 312
WIRE 144 312 16 312
WIRE 464 328 464 88
WIRE 464 328 208 328
WIRE 176 360 176 344
FLAG 576 -24 0
FLAG 64 24 0
FLAG -48 216 0
FLAG -176 -248 0
FLAG 336 200 0
FLAG 176 360 0
FLAG 336 264 0
FLAG -176 72 0
FLAG -272 88 0
FLAG -576 72 0
FLAG 496 -24 0
FLAG 288 -248 OUT
FLAG -576 -40 IN
SYMBOL voltage 576 -136 R0
SYMATTR InstName V1
SYMATTR Value 9
SYMBOL LT1018 64 -24 R0
SYMATTR InstName U1
SYMBOL res -64 -8 R0
SYMATTR InstName R1
SYMATTR Value 1Meg
SYMBOL res -64 104 R0
SYMATTR InstName R2
SYMATTR Value 10K
SYMBOL diode -144 120 R270
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL diode -64 -104 M180
SYMATTR InstName D2
SYMATTR Value 1N4148
SYMBOL res 48 -248 R0
SYMATTR InstName R3
SYMATTR Value 47K
SYMBOL diode -80 -264 R90
SYMATTR InstName D3
SYMATTR Value 1N4148
SYMBOL cap 192 -264 R90
SYMATTR InstName C1
SYMATTR Value .001
SYMBOL res 192 -360 R90
SYMATTR InstName R4
SYMATTR Value 3Meg
SYMBOL diode 240 -8 R270
SYMATTR InstName D4
SYMATTR Value 1N4148
SYMBOL res 320 -136 R0
SYMATTR InstName R5
SYMATTR Value 220K
SYMBOL diode 320 8 R0
SYMATTR Value 1N4148
SYMATTR InstName D5
SYMBOL zener 320 184 M180
SYMATTR InstName D6
SYMATTR Value LT1034
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL LT1018 176 312 M0
SYMATTR InstName U2
SYMBOL res 208 104 R0
SYMATTR InstName R6
SYMATTR Value 330K
SYMBOL cap 320 248 R90
SYMATTR InstName C2
SYMATTR Value .1
SYMBOL cap -192 40 M180
SYMATTR InstName C3
SYMATTR Value .1
SYMBOL npn -336 -24 R0
SYMATTR InstName Q1
SYMATTR Value 2N3904
SYMBOL res -224 296 R90
SYMATTR InstName R7
SYMATTR Value 100K
SYMBOL res -352 -56 R90
SYMATTR InstName R8
SYMATTR Value 1.2Meg
SYMBOL voltage -576 -40 R0
SYMATTR Value PWL(0 0 .5 1)
SYMATTR InstName V2
SYMBOL cap 96 88 R90
SYMATTR InstName C4
SYMATTR Value 220p
SYMBOL cap 464 -40 R90
SYMATTR InstName C5
SYMATTR Value 2.2
SYMBOL cap 96 200 R90
SYMATTR InstName C6
SYMATTR Value 100p