Version 4
SHEET 1 996 680
WIRE -208 96 -240 96
WIRE 96 96 -128 96
WIRE 656 96 320 96
WIRE 656 112 656 96
WIRE 96 176 64 176
WIRE 400 176 320 176
WIRE 544 176 400 176
WIRE 400 192 400 176
WIRE 544 192 544 176
WIRE 656 208 656 192
WIRE 0 256 -16 256
WIRE 96 256 80 256
WIRE 368 256 320 256
WIRE 368 288 368 256
WIRE 400 288 400 272
WIRE 400 288 368 288
WIRE 544 288 544 272
WIRE 400 304 400 288
WIRE 400 400 400 384
FLAG -240 96 0
FLAG 544 288 0
FLAG 656 96 PWMout
FLAG 656 208 0
FLAG 400 400 0
FLAG -16 256 0
FLAG 64 176 0
SYMBOL res 96 240 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 487K
SYMBOL res 384 288 R0
SYMATTR InstName R2
SYMATTR Value 1000K
SYMBOL res 384 176 R0
SYMATTR InstName R3
SYMATTR Value 392K
SYMBOL res 640 96 R0
SYMATTR InstName R4
SYMATTR Value 10K
SYMBOL voltage 544 176 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 3
SYMBOL voltage -112 96 R90
WINDOW 123 74 56 VTop 2
WINDOW 39 53 56 VTop 2
WINDOW 3 32 56 VTop 2
WINDOW 0 -32 56 VBottom 2
SYMATTR Value PULSE(0 1 10m 50m 50m 5m 110m)
SYMATTR InstName V2
SYMBOL SpecialFunctions\\LTC6992-1 208 176 R0
SYMATTR InstName U1
TEXT 536 384 Left 2 !.tran 120m startup
TEXT 208 56 Bottom 2 ;400Hz, 100% to 0% Duty Cycle\nSwept Pulse Width Modulated Output\nStartup Modeled