Version 4
SHEET 1 1044 680
WIRE -240 128 -240 112
WIRE -240 240 -240 208
WIRE -176 272 -176 144
WIRE -176 464 -176 352
WIRE -96 112 -240 112
WIRE -96 160 -96 112
WIRE -96 240 -240 240
WIRE -96 240 -96 224
WIRE -96 352 -96 240
WIRE -96 464 -176 464
WIRE -96 464 -96 416
WIRE -96 480 -96 464
WIRE -64 48 -80 48
WIRE -64 112 -96 112
WIRE -64 112 -64 48
WIRE -64 304 -64 112
WIRE -48 464 -96 464
WIRE -48 464 -48 176
WIRE -32 144 -176 144
WIRE -32 368 -32 144
WIRE 0 176 -48 176
WIRE 0 240 -96 240
WIRE 0 304 -64 304
WIRE 0 368 -32 368
WIRE 32 48 -64 48
WIRE 240 48 112 48
WIRE 240 144 -32 144
WIRE 240 144 240 48
WIRE 240 176 224 176
WIRE 240 176 240 144
WIRE 240 240 224 240
WIRE 240 304 224 304
WIRE 240 304 240 240
WIRE 256 368 224 368
WIRE 256 384 256 368
WIRE 256 464 -48 464
WIRE 256 464 256 448
WIRE 352 144 240 144
WIRE 352 192 352 144
WIRE 352 304 240 304
WIRE 352 304 352 272
WIRE 352 352 352 304
WIRE 352 464 256 464
WIRE 352 464 352 416
FLAG -96 480 0
FLAG -80 48 Out
IOPIN -80 48 Out
SYMBOL Robertugo\\555_ALL 160 288 R0
WINDOW 38 -75 81 Left 0
WINDOW 0 -62 -81 Left 0
SYMATTR SpiceModel tlc555
SYMATTR InstName U1
SYMBOL cap -112 352 R0
WINDOW 0 -43 9 Left 0
WINDOW 3 -35 62 Left 0
SYMATTR InstName Ctoff
SYMATTR Value 10n
SYMBOL cap 240 384 R0
WINDOW 0 21 8 Left 0
WINDOW 3 19 64 Left 0
SYMATTR InstName Cbp
SYMATTR Value 10n
SYMBOL voltage -176 256 R0
WINDOW 3 -13 59 Left 0
SYMATTR Value 12
SYMATTR InstName Vcc
SYMBOL diode -112 160 R0
WINDOW 0 -47 28 Left 0
WINDOW 3 -57 63 Invisible 0
SYMATTR InstName Doff
SYMATTR Value 1N914
SYMBOL res 128 32 R90
WINDOW 0 16 113 VBottom 0
WINDOW 3 -13 -12 VTop 0
SYMATTR InstName R1
SYMATTR Value 1k
SYMBOL res -256 112 R0
WINDOW 0 26 49 Left 0
WINDOW 3 27 88 Left 0
SYMATTR InstName Rtoff
SYMATTR Value {Val}
SYMBOL cap 336 352 R0
WINDOW 0 -43 9 Left 0
WINDOW 3 -35 62 Left 0
SYMATTR InstName Cton
SYMATTR Value 10n
SYMBOL res 336 176 R0
WINDOW 0 -39 31 Left 0
WINDOW 3 -89 61 Left 0
SYMATTR InstName Rton
SYMATTR Value {11k-Val}
TEXT 166 482 Left 0 !.tran 0 5m 0 2u startup
TEXT -928 144 Left 0 !.params: Vdd 12 Ronx=.1 \n.step param Val  1k 10k 1k\n.meas tran ta FIND time WHEN V(out)={Vdd/2} td=1m rise=1\n.meas tran tb FIND time WHEN V(out)={Vdd/2} td=1m rise=11\n.meas tran Frec PARAM 10/(tb-ta)\n.Meas tran Tc FIND time WHEN V(Out)={Vdd/2} td=1m fall=1\n.Meas tran Td FIND time WHEN V(Out)={Vdd/2} td=1m fall=2\n.Meas tran T1 Param  (Tc-Ta)\n.Meas tran T2  Param  (Td-Ta)\n.Meas tran Ton Param If (T1>0, T1, T2)\n.Meas tran Duty% Param  Ton*Frec*100