* SPICE netlist
R2 NC_01 NC_02 850
R3 NC_03 NC_04 6k1
C1 Vout 0 8p5
C2 N008 0 1p
R4 NC_05 NC_06 4k7
C3 Vp 0 10p
C4 Vp 0 10n
R1 NC_07 NC_08 850
C5 N009 0 1p
R5 NC_09 NC_10 4k7
C6 Vs 0 10n
R6 NC_11 NC_12 2k2
C7 N007 0 10n
D1 N007 N006 1N4148
D2 0 N007 1N4148
V2 N006 0 5
V1 N003 0 15kV
C8 N004 0 330p
S1 N004 N003 N001 0 ChargeSW
S2 N005 N004 N002 0 DischargeSW
R7 NC_13 NC_14 330
V3 N001 0 PULSE(0 5 0.1 0 0 0.2 1 1)
V4 N002 0 PULSE(0 5 0.35 0 0 1 1 1)
,model ChargeSW SW(Ron=0.0001 Roff=10Gig Vt=2.5 Vh=0.1)
,model DischargeSW SW(Ron=0.0001 Roff=10Gig Vt=2.5 Vh=0.1)
.tran 1.5

* LTspice schematic (.asc)
Version 4
SHEET 1 1744 832
WIRE -296 -416 -344 -416
WIRE 104 -416 56 -416
WIRE -296 -336 -296 -416
WIRE 104 -336 104 -416
WIRE -424 -288 -424 -416
WIRE -408 -288 -424 -288
WIRE -344 -288 -344 -416
WIRE -344 -288 -360 -288
WIRE -24 -288 -24 -416
WIRE -8 -288 -24 -288
WIRE 56 -288 56 -416
WIRE 56 -288 40 -288
WIRE -424 -240 -584 -240
WIRE -232 -240 -344 -240
WIRE -24 -240 -232 -240
WIRE 152 -240 56 -240
WIRE 424 -240 232 -240
WIRE -584 -192 -584 -240
WIRE -232 -192 -232 -240
WIRE -232 -64 -232 -128
WIRE 424 -64 -232 -64
WIRE -584 -48 -584 -112
WIRE -232 -48 -232 -64
WIRE -232 -48 -584 -48
WIRE -232 -16 -232 -48
WIRE -456 64 -584 64
WIRE -328 64 -456 64
WIRE -456 80 -456 64
WIRE -584 96 -584 64
WIRE -328 96 -328 64
WIRE -456 176 -456 160
WIRE -584 240 -584 176
WIRE -584 240 -872 240
WIRE -568 240 -584 240
WIRE -536 240 -568 240
WIRE -392 240 -456 240
WIRE -328 240 -328 160
WIRE -328 240 -392 240
WIRE -264 240 -328 240
WIRE -184 240 -264 240
WIRE -24 240 -104 240
WIRE 24 240 -24 240
WIRE 120 240 24 240
WIRE 200 240 120 240
WIRE 344 240 280 240
WIRE 376 240 344 240
WIRE 520 240 456 240
WIRE 616 240 520 240
WIRE 776 240 696 240
WIRE 872 240 776 240
WIRE -568 288 -568 240
WIRE -264 288 -264 240
WIRE -24 288 -24 240
WIRE 120 288 120 240
WIRE 344 288 344 240
WIRE 520 288 520 240
WIRE 776 288 776 240
WIRE -392 304 -392 240
WIRE 120 400 120 352
WIRE 344 400 344 352
WIRE 520 400 520 352
WIRE 776 400 776 352
WIRE -568 416 -568 352
WIRE -392 416 -392 368
WIRE -264 416 -264 352
WIRE -24 416 -24 352
FLAG 344 400 0
FLAG 776 400 0
FLAG 872 240 Vout
FLAG 120 400 0
FLAG -24 416 0
FLAG 520 400 0
FLAG -568 416 0
FLAG -264 416 0
FLAG 24 240 Vp
FLAG -872 240 Vs
FLAG -392 416 0
FLAG -456 176 0
FLAG -232 -16 0
FLAG 424 -240 Vs
FLAG -296 -336 0
FLAG 104 -336 0
SYMBOL res 296 208 R90
SYMATTR InstName R2
SYMATTR Value 850
SYMBOL res 712 208 R90
SYMATTR InstName R3
SYMATTR Value 6k1
SYMBOL cap 760 288 R0
SYMATTR InstName C1
SYMATTR Value 8p5
SYMBOL cap 328 288 R0
SYMATTR InstName C2
SYMATTR Value 1p
SYMBOL res -88 208 R90
SYMATTR InstName R4
SYMATTR Value 4k7
SYMBOL cap 104 288 R0
SYMATTR InstName C3
SYMATTR Value 10p
SYMBOL cap -40 288 R0
SYMATTR InstName C4
SYMATTR Value 10n
SYMBOL res 472 208 R90
SYMATTR InstName R1
SYMATTR Value 850
SYMBOL cap 504 288 R0
SYMATTR InstName C5
SYMATTR Value 1p
SYMBOL res -440 208 R90
SYMATTR InstName R5
SYMATTR Value 4k7
SYMBOL cap -584 288 R0
SYMATTR InstName C6
SYMATTR Value 10n
SYMBOL res -552 192 R180
SYMATTR InstName R6
SYMATTR Value 2k2
SYMBOL cap -280 288 R0
SYMATTR InstName C7
SYMATTR Value 10n
SYMBOL diode -312 160 R180
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL diode -376 368 R180
SYMATTR InstName D2
SYMATTR Value 1N4148
SYMBOL voltage -456 64 R0
SYMATTR InstName V2
SYMATTR Value 5
SYMBOL voltage -584 -208 R0
SYMATTR InstName V1
SYMATTR Value 15kV
SYMBOL cap -248 -192 R0
SYMATTR InstName C8
SYMATTR Value 330p
SYMBOL sw -328 -240 R90
SYMATTR InstName S1
SYMATTR Value ChargeSW
SYMBOL sw 72 -240 R90
SYMATTR InstName S2
SYMATTR Value DischargeSW
SYMBOL res 248 -272 R90
SYMATTR InstName R7
SYMATTR Value 330
SYMBOL voltage -440 -416 R270
SYMATTR InstName V3
SYMATTR Value PULSE(0 5 0.1 0 0 0.2 1 1)
SYMBOL voltage -40 -416 R270
SYMATTR InstName V4
SYMATTR Value PULSE(0 5 0.35 0 0 1 1 1)